01 February 2008

February 2008

A team of geologists believes it has found the incoming space rock's
impact crater, and dating suggests its formation coincided with the
celestial vision said to have converted a future Roman emperor to
Christianity.

It was just before a decisive battle for control of Rome and the
empire that Constantine saw a blazing light cross the sky and
attributed his subsequent victory to divine help from a Christian God.

Constantine went on to consolidate his grip on power and ordered
that persecution of Christians cease and their religion receive
official status.

Civil war

In the fourth century AD, the fragmented Roman Empire was being
further torn apart by civil war. Constantine and Maxentius were
bitterly fighting to be the sole emperor.

Constantine was the son of the western emperor Constantius Chlorus.
When he died in 306, his father's troops proclaimed Constantine emperor.

" ...a most marvellous sign appeared to him from heaven... " Eusebius

But in Rome, the favourite was Maxentius, son of Constantius' predecessor, Maximian.

With both men claiming the title, a conference was called in AD 308
that resulted in Maxentius being named as senior emperor along with
Galerius, his father-in-law. Constantine was to be a Caesar, or junior
emperor.

The situation was not a stable one, however, and by 312 the two men were at war.

Constantine overran Italy and faced Maxentius at the Milvian Bridge
over the Tiber a few kilometres from Rome. Both knew it would be a
decisive battle with Constantine's forces outnumbered.

'Conquer by this'

It was then that something strange happened. Eusebius - one of the
Christian Church's early historians - relates the event in his
Conversion of Constantine.

"...while he was thus praying with fervent entreaty, a most
marvellous sign appeared to him from heaven, the account of which it
might have been hard to believe had it been related by any other person.

"...about noon, when the day was already beginning to decline,
he saw with his own eyes the trophy of a cross of light in the heavens,
above the Sun, and bearing the inscription 'conquer by this'.

"At this sight he himself was struck with amazement, and his
whole army also, which followed him on this expedition, and witnessed
the miracle."

Spurred on by divine intervention, Constantine's army won the day
and he gave homage to the God of the Christians whom he believed had
helped him.

This was a time when Christianity was struggling. Support from the
most powerful man in the empire allowed the emerging religious movement
to flourish.

Like a nuclear blast

But what was the celestial event that converted Constantine and altered the course of history?

Jens Ormo, a Swedish geologist, and colleagues working in Italy believe Constantine witnessed a meteoroid impact.

Crater, Ormo The research team believes it has identified what remains of the impactor's crater.

It is the small, circular Cratere del Sirente in central Italy. It
is clearly an impact crater, Ormo says, because its shape fits and it
is also surrounded by numerous smaller, secondary craters, gouged out
by ejected debris, as expected from impact models.

Radiocarbon dating puts the crater's formation at about the right
time to have been witnessed by Constantine and there are magnetic
anomalies detected around the secondary craters - possibly due to
magnetic fragments from the meteorite.

According to Ormo, it would have struck the Earth with the force of
a small nuclear bomb, perhaps a kiloton in yield. It would have looked
like a nuclear blast, with a mushroom cloud and shockwaves.

It would have been quite an impressive sight and, if it really was
what Constantine saw, could have turned the tide of the conflict.

But what would have happened if this chance event - perhaps as rare
as once every few thousand years - had not occurred in Italy at that
time?

Maxentius might have won the battle. Roman history would have been
different and the struggling Christians might not have received state
patronage.

The history of Christianity and the establishment of the popes in Rome might have been very different.

Robert Simpson saw it from his home near Fort Davis and was delighted. But then, he had a better idea of what it was.

"It always kind of floors you," said Simpson, a spokesman for McDonald Observatory, 175 miles southeast of El Paso.

The meteor appeared at 12:47 p.m. as a flash about as bright as the surface of a setting sun, he said.

The reports -- of the light, an explosive blast and a smoke trail --
are all consistent with the appearance of a daytime meteor, also known
as a fireball or bolide.

"If it had happened at night it would have lit up the countryside as
bright as day," said Bill Wren, another observatory spokesman.

As it was, it was pretty spectacular.

Fire and police agencies in El Paso County and southern New Mexico
were flooded with reports of an explosion that shook homes and jangled
nerves.

A police helicopter flying about 25 miles east of the city spotted
about an acre of scorched ranch land, and authorities believe it could
be where the meteor hit. But the foreman of Cooper Cattle Co. ranch
said he didn't think so.

"We had two different fires out here a couple of days ago during the lightning storms," said Dub Pruitt.

Some residents saw the flash; others heard only a shuddering boom.

"It shook the whole damned neighborhood," said Tom Tyra, a Horizon City resident. "Everybody came out of their house."

A team of Korean scientists in Antarctica has discovered a large meteorite weighing 3.7 kg.

The Korea Polar Research Institute under the Korea Ocean Research
and Development Institute said Monday that the country's second
exploration team to Antarctica discovered 13 meteorites in the western
Thiel Mountains on Dec. 24, 29 and 30.

Last year, the country's first exploration team to the southern
continent found five meteorites, but they weighed only between 200 and
400 g.

Meteorites, large pieces of rocks from outer space that have landed
on Earth, are important in the study of the creation of the solar
system and the evolution of the planets.

Antarctica accounts for just three percent of the Earth's surface,
but over 80 percent or 25,000 of all discovered meteorites have been
found there.

With a total of 18 meteorites discovered by the two exploration
teams, Korea has become the fifth holder of meteorites after the U.S.,
Japan, China and Italy.

A space rock that smashed into Canada more than 200 million years
ago is being blamed for health risks faced today by several communities
in central Manitoba, according to a new international study of
groundwater quality around the ancient Lake St. Martin meteorite crater
north of Winnipeg.

In what's being described as the first-ever finding of a modern-day
health threat posed by a prehistoric meteorite strike, the researchers
say elevated levels of fluoride and other chemicals in the area's
groundwater can be traced to the shattering of subsurface granite when
the extraterrestrial object slammed into Earth nearly a quarter of a
billion years ago.

"The possibility that a meteor impact could devastate modern human
civilization is a real concern," especially given such events as the
dinosaur-killing strike on the Yucatan Peninsula 65 million years ago,
the researchers note in their study of the Lake St. Martin crater in
central Manitoba, published in the February issue of Geology.

"However, meteors may affect human populations through more subtle
routes in addition to these commonly recognized, catastrophic events."

Located between Lake Manitoba and Lake Winnipeg about 250 north of
Winnipeg, Lake St. Martin is believed to be the site of a meteorite
strike about 230 million years ago that left a 24-kilometre-wide
crater, now largely obscured by time.

Scientists recently theorized that the Manitoba site has sister
craters in France, Quebec, North Dakota and Russia - all created within
hours of each other when large pieces of a fragmented meteor struck
Earth.

For years, Canadian scientists have been trying to understand the
cause of poor water quality in the town of Gypsumville and two nearby
First Nations communities around Lake St. Martin. High levels of
fluoride, well beyond recommended health limits, have forced area
residents to seek alternative water supplies.

The new study - led by New Zealand-based geoscientist Matt Leybourne
and two of his former colleagues at the Geological Survey of Canada -
shows how shocked, fractured and melted rocks around the ancient impact
site allow fluoride to leach more easily into the area's groundwater.
Nearby rocks beyond the crater don't show the same leaching effect.

"It's a smoking gun that's been smoking for a long time,"
Ottawa-based scientist Jan Peter, co-author of the study, told Canwest
News Service. "We don't know of anybody else who's made that kind of a
link."

Elevated fluoride is "a major health issue in many parts of the
world" that can cause damage to teeth, softening of bones, calcified
tendons and ligaments and neurological damage, the study states.

Peter said the communities around Lake St. Martin have long been
aware of the groundwater contamination, but now have a clearer
explanation - reaching back to the Triassic age - of when the problem
began.

He added: "The best guesstimate is that the meteorite strike was
around 230 million years ago. That's a heck of a long time to still be
having its impact felt."

This week marks the golden anniversary of what is arguably the most
spectacular meteorite fall ever seen. At 10:40 a.m. on February 12,
1947, a incredibly bright fireball seared its way across the sky of
eastern Siberia and rained around 70 tons of iron meteorites onto the
rugged landscape. Because it was so well documented, the Sikhote-Alin
fall proved a great boon to meteorite science.

The 1947 Siberian event is considered in most literature as one of
the two most significant events this century where the earth has
encountered objects from space. It was an iron meteorite that broke up
only about 5 miles above the earth. It produced over 100 craters with
the largest being around 85 feet in diameter. The strewnfield covered
an area of about 1 mile by a half mile. There were no fires or similar
destruction like that found at Tunguska.

Shredded trees and broken branches mostly. A total of 23 tons of
meteorites were recovered and it's been estimated it's total mass was
around 70 tons when it broke up.

Gill - If the name "2007TK238" rings no bells, that would not be surprising.

What is surprising, however, is that it was students here at
Northfield Mount Hermon School, not some established astronomer, who
discovered an asteroid subsequently identified with that number-filled
name.

A trio of students in S. Hughes Pack's astronomy class, and Pack
himself, got official credit for discovering a group of asteroids while
working with the Center for Astrophysics in Cambridge. They used images
fed to their computers from a 32-inch telescope in Illinois.

The class pored over the images, primarily to give position reports
on asteroids that were already discovered, thereby enabling the center
to keep tabs on where the potentially lethal bodies were traveling, and
if they were a threat to Earth.

But the students, Wida Li from China, Josh R. Throckmorton from
Bedford, and Chelsea A. Bunker of South Deerfield, came up with some
blurry, small objects that weren't on anybody's list, and determined
they were previously unknown asteroids, which are rocks left over from
the creation of the solar system. Their finding was investigated and
confirmed by the center.

"Being able to step into the shoes of a professional astronomer, and
actually contribute to the world of science, is one of the coolest
things I have ever done," said Throckmorton.

And fortunately, the asteroids the students discovered are not headed this way.

"We don't want to be the ones to find the asteroid that hits Earth," Pack said.

Pack, in his classes, tries to impress upon the students the
enormity of the consequences should a large asteroid hit Earth, citing
it was an event that already happened, wiping out whole species of
life. He shows them Hollywood's "Armageddon," in which Bruce Willis
leads an expedition of miners to land on an oncoming asteroid to
successfully blow it up, a film full of scientific absurdities but
which gets the attention of students, he said.

There is little that could actually be done to deter an
asteroid, and only with knowing its exact course could an impact area
be evacuated, he said, to try to save some lives.

For Pack, as the teacher, the process is the thing.

"These are high school students doing real science. It is not easy and it is mundane - that's what real science is," he said.

Despite the tedium of the asteroid location and positioning work, the students found it thrilling.

"It was really fun, actually," said Bunker.

"It's good to know we are making a contribution while not even into college yet," Throckmorton said.

A meteorite slammed into a sparsely populated area of Honduras last
month, terrifying residents and leaving a 165-foot-wide crater,
scientists confirmed Sunday.

Villagers reported seeing a fireball crash and break into small red
and yellow pieces on Nov. 22 near San Luis, in the western province of
Santa Barbara. But Sunday's statement was the first official word that
the object was a meteorite.

Maria Cristina Pineda, a physicist from the National Autonomous
University of Honduras, said Sunday that the meteorite was composed of
materials that were 4 billion years old, Pineda said.

There was no word on the dimensions of the meteorite, but it was
much smaller than the size of the crater. Some 50,000 years ago, a
meteorite 180 feet wide smashed into northern Arizona and dug a crater
4,000 feet wide. And a 300-foot meteorite struck in Siberia in 1908,
leveling trees for miles.

Residents of San Luis, 125 miles west of the capital, were terrified
by the meteorite's crash, which sparked a fire that destroyed several
acres of coffee plants and damaged a main highway.

"We saw a large ball of fire, with a long tail that rapidly
descended from the sky and fell near San Luis, before our incredulous
eyes," said Elmer Adan Rivera, a teacher from the region.

"I arrived almost immediately to the site of the explosion," said
peasant Francisco Aguilar Sabillon. "There were enormous flames, and
everything was destroyed. Because of that I fled from the place,
frightened."

Authorities have asked those living nearby to stay away from the
crash site. The meteorite did not appear to have any properties that
would pose a threat to humans, they said.

Thursday Oct 3, 8:00pm Saw what appeared to be a low-altitude
fireball, heading north from the plains, into the southern end of the
Sangre de Cristos, just southeast of Santa Fe.

When I first saw it, it was in full glory; I don't know how much I
missed. It burned brilliant green, with active, changing head and tail,
for several (3-6) seconds, then disintegrated in a show of gold, into 4
or 5 smaller pieces, glowing white, spread out in a line, until they
seemed to burn out, another 3-5 seconds later.

Distance is of course unknown, to me it seemed that the final shards
were not far over the foothills. It seemed to be travelling as fast as
a low flying airplane.

Looking for another viewer, to help confirm position and height. Any one else happen to see it?

It was surely the most thrilling 10 seconds of my five years of amateur viewing!

Part 2: A bird? A plane?

A brilliant meteor seen in the skies of the western U.S. on the
evening of October 3 was likely a piece of an asteroid or comet, or
even a piece of space junk, astronomers said.

The meteor was seen from California to New Mexico at around 9pm PDT
(4am GMT October 4). It was described by many as a long green streak
bright enough to light up sky for several seconds. Hundreds of people
contacted local authorities, believing the streak to be the result of a
mid-air plane accident. The flash, however, took place too high to be
possibly caused by a plane.

John Mosley, an astronomer at the Griffith Park Observatory in Los
Angeles, attributed the flash to a chunk of comet or asteroid material
that burned up in the Earth's atmosphere. JPL officials added the
possibility that the meteor was a piece of space junk reentering the
Earth's atmosphere. No debris from the meteor was found on the ground.

Part 3: A reward of 5000 $

The University of California at Los Angeles (UCLA) offers a reward
of 5.000 $ for a piece weighing 100 g or more of the meteorite fallen
on October 3, 1996. Some scientists say that the bolide bounced in the
upper atmosphere. Loud sonic booms were heard and probably some
fragments fell to the ground before the bolide returned to the space.

PASADENA- Should anyone be inclined to do a bit of meteorite hunting
this weekend for a $5,000 reward, Caltech seismologist Kate Hutton
thinks she can provide some help.

According to Hutton, any larger chunks from the meteor that lit up
the Western skies on the night of Oct. 3 may have landed in the Rose
Valley area near Little Lake. Hutton figured this out by analyzing data
from 31 of the seismic stations belonging to the Southern California
Seismographic Network (operated by Caltech and the U.S. Geological
Survey). "As it fell, the atmospheric drag caused the meteroid to
explode in mid-air at least twice," Hutton says. "The explosions
generated sound waves in the air similar to a sonic boom, which were
detected by the seismographs. Using a procedure that is very similar to
the one used to locate earthquakes underground, I used the arrival
times of the sound waves at the various seismic stations to estimate
where the explosions occurred." Two of the explosions were well
located, Hutton adds. Both were 20 to 30 miles above the Fivemile
Canyon area in the eastern Sierra foothills. The explosions were
separated by about 25 seconds, and the second was about five miles
lower than the first and about a mile further eastward. Based on this
data and on eyewitness accounts provided by John Wasson of UCLA and
Mark Boslough (Ph. D. from Caltech, 1984) of Sandia National Laboratory
in New Mexico, Hutton thinks that any larger fragments that survived
the firey entry into Earth's atmosphere would have landed to the
east-northeast of the explosions, perhaps in the Rose Valley area near
Little Lake. Smaller fragments may have fallen more or less straight
down from where the explosions occurred.

The Little Lake area would probably be the more seductive area to
search, and for a very good reason. UCLA has offered a $5,000 reward
for the first fragment that weighs at least four ounces.

Hutton says the seismographic instruments didn't pick up a meteorite
impact on Earth, but this is not surprising, since a single fragment
would probably have to weigh several tons in order for its impact to be
detected. The term "meteorite," by the way, refers to chunks of
extraterrestrial debris that survive the entry into the atmosphere and
end up on the ground. "Meteoroids" are chunks that travel through
space, while "meteor" is the proper designation for the light show
produced by a rock from outer space slowing down in the Earth's
atmosphere.

Any surviving meteorite fragments would probably have a fresh black
matte crust. If the meteorite struck something on the ground, part of
the crust might have chipped off to reveal a lighter interior. If
anyone finds a meteorite fragment weighing at least four ounces, he or
she should get in touch with Dr. John Wasson at UCLA. Wasson's e-mail
address is wasson@igpp.ucla.edu.

Contact: Robert Tindol (818) 395-3631 tindol@caltech.edu

Part 5: A year later

Meteorite Falls From Oct 1996

From: Ron Baalke

Date: Wed, 8 Oct 1997 14:14:51 GMT

NEWS RELEASE OCT. 1, 1997

Albuquerque, N.M. After a year of detective work involving scores of
eyewitness reports from across New Mexico and Texas, a group of
scientists has concluded that the Earth collided with a swarm of cosmic
debris on the night of Oct. 3-4, 1996.

The most widely-reported fireballs were ones over eastern New Mexico
and the Texas panhandle, and another near Bakersfield, California,
exactly 104 minutes later. The relationship among the times, locations,
and trajectories of the meteors seemed too unlikely to be mere
coincidence, and had initially led some scientists to believe that a
single object skimmed through the atmosphere and re-entered after a
single orbit.

After careful analysis of a videotape taken from El Paso, Texas,
together with eyewitness reports, Mark Boslough of Sandia National
Laboratories and Peter Brown of the University of Western Ontario found
that the first meteor entered at too steep of an angle to skip off the
atmosphere. They are now convinced that the two fireballs observed over
New Mexico/Texas and over California were two different objects.

They also determined the most likely location in the Texas panhandle
where meteorites might have fallen, and John Wasson (UCLA) has
re-issued a reward for a sample. Brown and Boslough believe that any
meteorites reaching the ground in the Southwest would most likely be
found south of Amarillo, near the towns of Hereford and Canyon, where
they were carried by winds to the east of the visible trajectory. The
most likely place for small meteorites to have landed would be in an
oblong area about 10 miles ESE if Hereford, but any larger meteorites
would be in a strip that stretches as far as 10 miles east of Canyon.

This part of the Texas Panhandle is well-known for its abundance of
meteorite finds because it is flat, with little vegetation and few
natural rocks on the surface. The most famous area is southwest of
Plainview, where over 900 meteorites were recovered after they fell in
1903, and were still being found as late as 1949.

Over the past year, two groups of scientists from Los Alamos
National Laboratory and the National Oceanic and Atmospheric
Administration have also reported low-frequency sound data showing that
the Earth's atmosphere was hit by at least 60 objects within several
hours of the two that were originally reported, two of which were also
observed by Defense Department satellites.

Most of the infrasound-producing meteors occurred during daylight
hours and were not seen by witnesses, but the large number of
collisions taking place that night helps explain why two bright ones
with such similar trajectories would be seen so closely spaced in time.
Although the scientists eliminated their hypothesis of a single object
bouncing off the atmosphere and re-entering it later, they are still
very interested in the events of one year ago because it means the
Earth collided with a cluster of objects, perhaps pieces of a broken
asteroid. A sample of one of these meteorites would help scientists
determine what kind of asteroid spawned the fragments and better
understand how they break apart and explode in the atmosphere, says
Sandia's Mark Boslough.

Prof. John Wasson is seeking such samples and is offering a reward
of $2,000 for the first confirmed sample as large as 4 ounces, and he
urges persons living within the calculated fall area to look in their
fields, on the roofs of buildings, in stock tanks and other locations
where stones would not be expected. Meteorite hunters are reminded to
get permission of land owners, and that any stones automatically belong
to the owner of the property on which it is found. The stones are most
likely to be black with a fresh matte texture. Samples should be sent
to Prof. Wasson at the Institute of Geophysics, UCLA, Los Angeles, CA
90095, or to Dr. Adrian Brearley, Institute of Meteoritics, University
of New Mexico, Albuquerque, NM 87131. Each sample will be acknowledged,
but those that are not meteorites will not be returned unless a return
self-addressed envelope is provided.

Part 6: Coincidence?

* October 3, 1815:

o In 1815, a meteorite was observed to fall from the sky in
Chassigny, France, after loud sonic booms were heard. The Chassigny
meteorite was later identified as a Mars meteorite and was the first
Mars meteorite ever found. Although it was estimated that the meteorite
originally weighed about 4,000 grams (~9 pounds), and there is only
about 570 grams preserved of the meteorite today. Chassigny is
distinctly different from the other Mars meteorite, so it has been
assigned its own signature subgroup, chassignite. Since so little of
Chassingy was preserved, and it is the only meteorite in its subgroup,
the Chassigny meteorite is the rarest of the Mars meteorites.

* October 3, 1962:

o A meteorite landed near Zagami, Nigeria about 10 feet away from a
farmer who was trying to chase crows from his corn field. The farmer
heard a tremendous explosion and was buffeted by a pressure wave. After
a puff of smoke and a thud, the meteorite buried itself in a hole about
2 feet deep. The Zagami meteorite was later identified as a Mars
meteorite. Weighing at about 18,000 grams (40 pounds), the Zagami
meteorite is the largest single individual Mars meteorite ever found.

There is evidence that there were two massive bolide explosions
which occurred over South America in the 1930's. One seems to have
occurred over Amazonia, near the Brazil-Peru border, on August 13,
1930, whilst the other was over British Guyana on December 11, 1935. It
is noted that these dates coincide with the peaks of the Perseids and
the Geminids, although any association with those meteor showers is
very tentative. The identification of such events is significant in
particular in that they point to the need for re-assessment of the
frequency of tunguska-type atmospheric detonations.

In 1989 an article by N.Vasilyev and G.V. Andreev in the IMO Journal(1) drew attention to a discussion, published in 1931 by L.A. Kulik
(2), of a possible Brazilian counterpart to the Tunguska bolide
explosion of 1908. The Brazilian event, which occurred on August 13,
1930, was described in the papal newspaper L'Osservatore Romano,
the report being derived from Catholic missionaries working in
Amazonia. That report, in Italian, was used as the basis of a
front-page story in the London newspaper The Daily Herald (since closed
down), which was published on March 6, 1931, and then seen by Kulik.
(For the interested reader, a copy of the story is reprinted in the
December 1995 Journal).

The locality of the explosion gives it it's name: The Rio Curaca event. This is close to the border between Brazil and Peru, at Latitude: 5 degrees South, Longitude: 71.5 degrees West.

Both of these newspaper stories were discussed in a recent paper by
Bailey and co-workers (4), who provide an English translation of the
story which appeared in L'Osservatore Romano. Since that paper should
be accessible to many readers of WGN, I will not give an extensive
account of it here. I will, however, just mention that although the
eye-witness accounts give do cover the phenomena which one might expect
to be produced by a massive bolide, there are some other interesting
reported observation which would require some explanation. These
include the following:

* An ear-piercing "whistling" sound, which might be understood as
being a manifestation of the electrophonic phenomena which have been
discussed in WGN over the past few years.

* The sun appearing to be "blood-red" before the explosion. I
note that the event occurred at about 8h local time, so that the bolide
probably came from the sunward side of the earth. If the object were
spawning dust and meteoroids-- that is, it was cometary in
nature--then, since low-inclination, eccentric orbits produce radiants
close to the sun, it might be that the solar coloration (which, in this
explanation, would have been witnessed elsewhere) was due to such dust
in the line of sight to the sun. In short, the earth was within the
tail of the small comet, if this explanation is correct.

* There was a fall of fine ash prior to the explosion, which
covered the surrounding vegetation with a blanket of white: I am at a
loss with regard to this, if the observation is correct (and not
mis-remembered as being prior-, rather than post-impact).

Bailey et al. also discuss the fact that the Rio Curaca event
occurred on the day of the peak of the annual Perseid meteor shower,
but conclude that this is likely to be purely a coincidence. The date
is also close to august 10, on which day in 1972 a large bolide was
filmed skipping through the upper atmosphere above western Wyoming and
Montana, departing from the earth above Canada (4). Again, this may be
merely a coincidence.

A brief discussion of the event is also given by R. Gorelli in august 1995 issue of Meteorite! magazine.

I now move on to the suspected explosion over British Guyana in
1935. The main source for information on this event is a story entitled
Tornado or Meteor Crash? in the magazine The Sky (the forerunner of Sky and Telescope)
of September 1939(5). A report from Serge A. Korff of the Bartol
Research Foundation, Franklin Institute (Delaware, USA) was printed, he
having been in the area--the Rupununi region of British Guyana--a
couple of months later. The date of the explosion appears to have been
December 11, 1935, at about 21h local time. I might note that this is
near the date of the peak of the Geminid meteor shower, but yet again
this may be merely a coincidence. The location is given as being near
Lat: 2 deg 10min North, Long: 59 deg 10 min West, close to Marudi
Mountain.

Korff's description suggested that the region of devastation might
be greater than that involved in the Tunguska event itself. On his
suggestion, a message was sent to William H. Holden, who in 1937 was in
the general region with the Terry-Holden expedition of the American
Museum of Natural History. That group hiked to the top of Marudi
Mountain in 1937 November and reported seeing an area some miles across
where the trees had been broken off about 25 feet above their bases,
although regrowth over two years in this tropical jungle had made it
difficult to define the area affected. Holden confirmed, on returning
to New York, that he believed the devastation was due to an atmospheric
explosion of cosmic origin. An explorer and author, Desmond Holdridge,
also visited the region in the late 1930's and confirmed the suspicion
that a comet or asteroid detonation was responsible.

Korff obtained several local reports, the best being from a Scottish
gold miner, Godfrey Davidson, who reported having been woken by the
explosion, with pots and pans being dislodged in his kitchen, and
seeing a luminous residual trail in the sky. A short while later,
whilst prospecting, he cam across a devastated region of the jungle he
estimated to be about five by ten miles (8 by 16 kilometers), with the
trees all seeming to have been pushed over.

Holden was unsure of the origin of the flattening of the forest, and
pointed out that similar destruction can result from tornados.
Holdridge, however, reported eye-witness accounts in accord with a
large meteoroid/small asteroid entry, with a body passing overhead
accompanied by a terrific roar (presumably electrophonic effects),
later concussions, and the sky being lit up like daylight. A local
aircraft operator, Art Williams, reported seeing an area of forest more
than twnety miles (32 kilometers) in extent which had been destroyed,
and he later stated that the shattered jungle was elongated rather than
circular, as occurred at Tunguska and would be expected from the air
blast caused by an object entering away from the vertical (the most
likely entry angle for all cosmic projectiles is 45 degrees).

There is a report of the Guyanan event, largely derived from the account in The Sky, in the newsletter Meteor Newsfor March 1974. Apparently as a result of that, the publishers (Karl
and Wanda Simmons, of Callahan, Florida) had some correspondence with a
Mr. F.A. Liems of Paramaribo, Surinam, concerning a possible
crater/event at Wahyombo in that country; he gives the location as Lat:
5.25 deg North, Long: 56.05 deg West. The letters date from 1976;
apparently Liems died in 1982. In 1990, as a result of Andreev's
article in WGN about the Brazilian event, Wanda Simmons sent
copies to him, and he kindly sent copies on to me. Various
notes/maps/letters are included, but it is difficult to know what to
make of them: my impression is that this concerns something that
occurred some time ago, not in this century, and it's linkage with an
incursion by an asteroid or comet is far from clear.

Below is the wording of the Newspaper article printed in The Daily Herald on March 6, 1931.

+ MENACE OF METEORS LIKE HUGE BOMBS FROM SPACE

+ HURRICANE OF FLAME

+ BLAZING BOLTS FIRE FORESTS

+ MANKIND'S LUCK

Another colossal bombardment of the earth from outerspace has just been revealed.

Three great meteors, falling in Brazil, fired and depopulated hundreds of miles of jungle.

News of this catastrophe has only now reached civilization because the meteors fell in the remote S. American wilderness.

It was yet another lucky escape of mankind from an appalling and unrealized peril.

The last great meteor fell in Siberia in 1908. In a district so
remote that only last year were details of it's destruction given to
the world. Had either of these two meteor falls chanced to strike a
city in a densely populated country, frightful loss of life and damage
would have been cuased. "A Meteor", Mr. C.J.P. Cave an ex-president of
the Royal meteorological Society stated recently "carries in front of
it a mass of compressed and incandescent air.

When it strikes the earth, this air "splashes" in a hurricane of
fire...The Brazilian meteors are reported (says the Central News) by
Father Fidello of Aviano. writing from San Paulo de Alivencia in the
state of Amazonas, to the papal newspaper, "Osservatore Romano".

BLAZING FOREST The meteors fell almost simultaneously during an
amazing storm. Terrific heat was engendered. Immediately they struck
the ground the whole forest was ablaze.

The fire continued uninterrupted for some months, depopulating a
large area. The fall of the meteor was preceded by remarkable
atmospheric disturbances. At 8 o'clock in the morning the sun became
blood-red and a penumbra spread all over the sky, producing the effect
of a solar eclipse. Then an immense cloud of reddish powder filled the
air and it looked as if the whole world was going to blaze up.

WHISTLING SOUND The powder was succeeded by fine cinders which
covered trees and vegetation with a blanket of white. There followed a
whistling sound that pierced the air with car-breaking intensity, then
another and another.

Three great explosions were heard and the earth trembled. The
Siberian meteor of 1908 completely destroyed the forest over an area of
70 miles in diameter. It's roar was heard 600 miles away and it's glare
maintained twilight all night even in England.

No, not when you see a ghost - but when you spot a meteorite falling from the sky.

It happens more often than you would think.

When a suspected meteorite landed on a Spruce Grove golf course
recently, a number of residents continued to come forward with their
own stories.

LOUD

"We both heard a very loud sound," Jocelyn and Michael Pederson
wrote in an e-mail, describing the incident. "It was like a plane
descending, and we thought a plane may have crashed.

"It was very close."

Mike Elliott, 49, his wife and a friend were headed south toward
Spruce Grove around that time when, "all three of us saw the same
thing."

"Its trajectory was straight down, and it was greenish in colour
with a white spot, leaving somewhat of a tail behind it," Elliott said.
"It surprised all of us, and we all thought it had to be a meteorite."

Elliott said it was the third meteorite he's spotted in his life - while veteran stargazer Evelyn Jones claims two.

Jones, who lives outside Breton, described driving home recently and
also suddenly "looking up at the sky and seeing this thing with a big
tail coming from behind a row of 60-foot spruce trees," - describing a
glowing object resembling a honeydew melon.

"I'm 64," she said when asked her age, adding, "and I'm of sound mind."

Alan Hildebrand, a professor at the University of Calgary, tracks
meteorites, or "fireballs," for the Canadian Space Agency as part of
his study of asteroids and comets. And he concedes there can be a
reluctance to report them.

"People do often tell me things like, 'I went into work and told
them what I saw, and they told me I was crazy,' " he said. "So, I
suppose they do have cause for fear.

"But that is another reason to report sightings because then other people might come forward, too."

But Hildebrand says that some 70 meteorites do indeed fall on
Canadian soil or water every year. And he adds that's where
organizations like the Meteorite and Impacts Advisory Committee come
in. The committee maintains a website [HERE], which includes online reporting forms.

FIREBALLS

Barring that, Hildebrand said people spotting fireballs may also
simply tell staff at institutions like the Telus World of Science, who
can pass on details to him.

The geology professor says besides assisting researchers understand
how the solar system works, reporting meteorites can help rule out
catastrophes like plane crashes.

Hildebrand recommends would-be reporters take notes on aspects like
height, distance and direction - and not rely on memory alone.

"Tracking down a meteorite is like the police trying to solve a crime," he said. "It's good to have multiple witnesses."

For nearly one and a half centuries, the cause of the most
notorious fire in U.S. history has been a source of "heated"
controversy. Some researchers suggest that a disintegrating comet
ignited the blaze. But the electrical theorists say that evidence most
often ignored offers the best clues.

"With the heat increased the wind, which came howling across the
prairie, until at last there arose a perfect hurricane. Mighty flakes
of fire, hot cinders, black, stifling smoke, were driven fiercely at
the people, and amid the terrible excitement hundreds of them had their
very clothes burned off their backs, as they stood there watching with
tearful eyes the going down of so many houses". -- James Goodsell's
History of the Great Chicago Fire, October 8, 9, and 10, Published 1871
by J.H. and C.M. Goodsell.

Sunday evening, October 8, 1871 marked the beginning of one of the
most devastating fires in U.S. history. Legend has it that "The Great
Chicago Fire" resulted from an agitated cow kicking over a lantern in
"Mrs O'Leary's barn". The dry leaves and parched wood of Illinois in
early autumn were the perfect kindling for a wildfire, and the fire
spread with extraordinary rapidity, consuming homes and buildings,
leaping from rooftop to rooftop with the speed of a locomotive. Between
October 8 and 10, an estimated 350 people perished. The fire destroyed
the homes of up to one-third of the city's population, about 1,600
stores, 60 factories, and 28 public buildings. Four square miles of the
city burned to the ground.

Contrary to popular folklore, the Chicago fire is not the worst in U.S. history. It was not even the worst to occur on October 8 that year.The same evening - in fact, at the same time, about 9:30 - a fierce
wildfire struck in Peshtigo, Wisconsin, over 200 miles to the north of
Chicago, destroying the town and a dozen other villages. Estimates of
those killed range upward from 1200 to 2500 in a single night. It was
not the Chicago fire but the simultaneous "Peshtigo Fire" that was the
deadliest in U.S. history.

And there is more. On the same evening, across Lake
Michigan, another fire also wreaked havoc. Though smaller fires had
been burning for some time - not unusual under the reported conditions
- the most intense outburst appears to have erupted simultaneously with
the Chicago and Peshtigo fires. The blaze is said to have then burned
for over a month, consuming over 2,000,000 acres and killing at least
200.

Concerning the Michigan outburst, it is reported that numerous fires
endangered towns across the state. The city of Holland was destroyed by
fire and in Lansing flames threatened the agricultural college. In
Thumb, farmers fled an inferno that some newspapers dubbed, "The Fiery
Fiend." Reports say that fires threatened Muskegon, South Haven, Grand
Rapids, Wayland, reaching the outskirts of Big Rapids. A steamship
passing the Manitou Islands reported they were on fire.

There can be no doubt that weather conditions at the time favored
wildfires. But never before, and never since, has the U.S. seen such
wildly destructive simultaneous conflagrations. This
"coincidence", combined with many unusual phenomena reported by
eyewitnesses, has led some to conclude that an extraordinary force, one
not of the earth, was a more likely "arson" than either a misbehaving
cow or a regional drought.

In 1883, Ignatius Donnelly, author of Ragnarok: the Rain of Fire and Gravel,
suggested that in early historic times our Earth suffered great
catastrophes from cometary intruders. To this claim he added: "There is
reason to believe that the present generation has passed
through the gaseous prolongation of a comet's tail, and that hundreds
of human beings lost their lives". He was referring to the
conflagration of 1871.

Is there plausible evidence that a comet may have caused the Chicago
fire and its regional counterparts? In 1985, Mel Waskin, who had
earlier discovered Donnelly's work, published a book, Mrs. O'Leary's Comet,
suggesting that a comet did indeed spark the October 8th fires. More
recently, Robert Wood, a physicist and aeronautical engineer formerly
with Douglas Aircraft and McDonnell Douglas, gained attention from the
Discovery Channel and other media for proposing the same idea.

The proponents of the cometary explanation cite many fascinating
details confirmed by eye witness reports: the descent of fire from the
heavens, a great "tornado" of fire rushing across the landscape and
tearing buildings from their foundations, descending balls of fire, a
rain of red dust, great explosions of wind accompanied by blasts of
thunder, buildings exploding into flame where no fire was burning, and
a good deal more. Some of the parallels with the later Tunguska event
are impossible to miss.

It seems that the records of the conflagration hold many clues that
are almost never mentioned in scientific discussion of the Chicago
fire. Over time the clues have virtually disappeared. They have
disappeared because they are not meaningful to minds conditioned by
popular ideas about how the "Chicago fire" started and what is
"scientifically" possible. Within these habits of perception, the most
important evidence will often go unnoticed or unremembered.

Where was Comet Biela?

A strange thing happened to comet Biela in 1845. The nucleus of
the comet split into two partners. The "smaller" comet (lower left in
the picture above), subsequently became more active and brighter than
the larger. And that was only the beginning.

In 1883, twelve years after the Chicago fire, Ignatius Donnelly published a widely read book, Ragnarok: the Rain of Fire and Gravel.
Though the book dealt primarily with the evidence for cometary
disasters in ancient times, Donnelly suggested that the Chicago fire
provided a small glimpse of the terror experienced by our earlier
ancestors. "There is reason to believe that the present generation has
passed through the gaseous prolongation of a comet's tail, and that
hundreds of human beings lost their lives".

Reflecting on the simultaneous events around Lake Michigan on the
evening of October 8, 1871, Donnelly posed the underlying mystery: "At
that hour, half past nine o'clock in the evening, at apparently the
same moment, at points hundreds of kilometers apart, in three different
states, Wisconsin, Michigan, and Illinois, fires of the most peculiar
and devastating kind broke out, so far as we know, by spontaneous
combustion". (We take up the historic testimony cited by Donnelly and
others in tomorrow's "Picture of the Day").

Donnelly believed he could identify the cause of the devastation. He
said it was Comet Biela, a comet that captured attention from
astronomers in 1826, returned for a few predictable visits, broke into
two nuclei, and then disappeared.

The comet was named after Austrian officer W. von Biela, who
observed the body in February 1826. By following the path of Biela, the
French astronomer Marie-Charles-Théodore de Damoiseau estimated the
time of its return. He said the comet would cross the orbit of the
Earth about one month ahead of our planet's arrival at the same spot.

Donnelly does not mention that ten days after Biela's announcement,
a French astronomer John Felix Adolphe Gambart also sighted the comet.
Both Biela and Gambert calculated the orbit, recognizing that earlier
comet apparitions in 1772 and 1805 were the same object that appeared
in 1826. And Gambert, along with other astronomers, predicted that the
comet would strike the earth on its return, which he projected for October 29, 1832.

Damoiseau's prediction was correct. Earth missed the comet by about a month.

On its anticipated 1846 return, Biela was first sighted in late 1845
as it moved toward perihelion (its closest approach to the Sun),
astronomers were surprised to see that the head of the comet had
acquired a faint satellite. It had split in two (picture above),
something we now know to be fairly common for comets, but still
mysterious to cometologists. In 1845, the event seemed unprecedented.
As noted by Carl Sagan and Nancy Druyan in their book Comet,
"the finding was so bizarre that the first astronomer to note this
twinning dismissed it as some internal reflection in his telescope".

In Robert Chapman's and John Brandt's The Comet Bookcertain details of Biela's return are fascinating. The discovery of a
partner occurred on January 13, 1846, when "a faint satellite comet was
observed a small distance from the main comet". Two tails were seen
parallel to each other. "Over the next month the fainter of the two
comets increased in brightness and finally became brighter than the
'main' comet. The situation then reversed and the main comet became the
brighter one again. In addition, the main comet grew a second tail and a luminous bridge of material joined the two comets"
[emphasis ours]. At this time the two nuclei were apart an estimated
250,000 kilometers, about two thirds of the distance separating Earth
and the Moon.

Donnelly's account at this point diverges from the history told by
Chapman and Brandt. As Donnelly tells it, "In 1852, 1859, and 1866, the
comet should have returned, but it did not". But Chapman and
Brandt - prominent figures at NASA's Goddard Space Flight Center at the
time of their book's publication - say that the twin comet-heads did
indeed appear at the appointed time in 1852. This reappearance is, in
fact, well documented. And one detail in Chapman's and Brandt's account
rarely shows up in standard discussions of cometology:

"...Both comets returned at the predicted time, though they were over 2 million kilometers apart [emphasis ours]. Once again the two comets took turns as the brighter of the pair. On at least one occasion a bright jet was seen between the two heads" [emphasis ours].

Though Sagan and Druyan report the splitting of Biela, they do not
mention the jet, an event for which the standard view of comets has no
theoretical reference.

The rest of Donnelly's discussion of Biela is in general agreement
with the summary by Chapman and Brandt. Amazingly, and with the aid of
a startling and unpredicted meteor shower on November 27, 1872,
Professor W. Klinkerfues of Berlin, calculated the trajectories of the
meteoric falls, concluding that they were the remains of the comet.
This, in turn led him to send instructions to Norman Pogson, Government
Astronomer at the Madras Observatory in India (far enough south to
allow a good view). Pogson's answer to Klinkerfues, dated December 6,
said he "found Biela immediately" on the first clearing of the sky, and
on the second day he saw it again. It showed no tail, he said.

As Chapman and Brandt put it, this was either an "incredible coincidence", or it was the actual last view of the comet.

The spectacular meteor shower that inspired Klinkerfues to identify
it with Biela has long since become an annual event - sort of - called
the Andromedids. And astronomers do not hesitate to connect the shower
to Biela. Each year the Earth passes through the remains of the comet,
but with widely varying consequences. And the effect today is trivial
by comparison with the November 1872 occurrence. Today the shower peaks
around mid-November, averaging less than three meteors per hour -
hardly deserving the title "shower". On the night of November 27, 1872,
however, records show several thousand meteors per hour - a direct and obvious link to the disintegration of the comet.

It remains to be asked, then, whether the fragmentation of Biela, a
comet on a path intersecting the orbit of the Earth, and predicted by
some astronomers to collide with the Earth in 1832, might
have been the source of the "great conflagration" in 1871. The comet
had split at least 25 years earlier (the 1846 appearance), and the two
partners had separated by more than 2 million kilometers by 1852. So
whether or not Klinkerfues observed Biela after the spectacular shower
of November 1872, we know he did not report seeing twobodies. Hence, at least one of the partners intersecting Earth's path
had presumably already disintegrated entirely, leaving the possibility
that on a subsequent orbit the Earth moved into debris left by the body.

The facts on the Andromedids, including their erratic occurrence
over the years and the obvious dispersal and depletion of the cometary
debris over a century and a half, cannot give us a definitive answer to
Donnelly's views on Biela. But as for plausibility, the answer is
definitive. Many facts are consistent with the interpretation, and
there are no facts that exclude the interpretation.

Of course, it is not necessary to identify an intruder, in order to
see the evidence of an intrusion. No one questions the exploding
Tunguska comet, asteroid or meteor on the basis that astronomers cannot
identify the incoming object.

But of all the scientific details about comet Biela, perhaps none
stands out more dramatically than the fact almost never mentioned - a
jet forming between the two nuclear fragments when they were 2 million
kilometers apart. In the purely gravitational and mechanical terms that
astronomers have sought to apply to comets, this jet is inconceivable.
But when we remember how inconsequential is gravity in the presence of
the electric force, the improbability disappears.

In fact, the jet is a clue more vital by far than the popular
"scientific" commentary on Donnelly's hypothesis. By directing our
attention to the electrical nature of comets, it also invites us to
look again at the historic testimony, with an eye to details long
unnoticed or forgotten.

Human Testimony Reconsidered

All investigators of the Chicago fire and its devastating
regional counterparts rely on human testimony. But how should we view
such testimony when it suggests things that are not currently believed?
Good science will not ignore witnesses when, in unison, they suggest
new lines of investigation.

On the evening of October 8, 1871 devastating fires erupted at
virtually the same moment in three different states in the region of
the Great Lakes - Wisconsin, Illinois, and Michigan. The outbursts
included the notorious "Chicago fire", but also an even more
devastating fire in Wisconsin, the worst in U.S. history, covering some
400 square miles. At the same time, wildfires also erupted across much
of Michigan. In his book Ragnarok: The Age of Fire and Gravel,
published in 1883, Ignatius Donnelly proposed that the simultaneous
outbursts were no coincidence; they were the effect of our Earth
meeting up with a fragment, or fragments, of comet Biela, a body that
had disintegrated a few years earlier while on an Earth-threatening
path.

As Donnelly reports it, in the Wisconsin fire near Lake Michigan, a
large area including the town of Peshtigo and several neighboring
cities was "swept bare by an absolute whirlwind of flame". His review
of the event, based on eyewitness accounts, was taken primarily from
the book "History of the Great Conflagration", by James W. Sheahan and
George P. Upton (1871). It includes the following report:

"At sundown there was a lull in the wind and comparative stillness.
For two hours there were no signs of danger; but at a few minutes after
nine o'clock, and by a singular coincidence, precisely the time at
which the Chicago fire commenced, the people of the village heard a
terrible roar. It was that of a tornado, crushing through the forests.
Instantly the heavens were illuminated with a terrible glare. The sky, which had been so dark a moment before, burst into clouds of flame.A spectator of the terrible scene says the fire did not come upon them
gradually from burning trees and other objects to the windward, but the
first notice they had of it was a whirlwind of flame in great clouds from above the tops of the trees, which fell upon and entirely enveloped everything". [Emphasis ours]

For many of the witnesses it seemed as if the biblical "last days"
had come. Though well accustomed to wildfires, they had seen nothing
like this before. "They could give no other interpretation to this
ominous roar, this bursting of the sky with flame, and this dropping
down of fire out of the very heavens, consuming instantly everything it
touched".

Donnelly continues quoting from Sheahan and Upton: "No two give a
like description of the great tornado as it smote and devoured the
village. It seemed as if 'the fiery fiends of hell had been loosened',
says one. 'It came in great sheeted flames from heaven', says another. 'There was a pitiless rain of fire and SAND. The atmosphere was all afire'. Some speak of 'great balls of fire unrolling and shooting forth, in streams'. The fire leaped over roofs and trees, and ignited whole streets at once". [Emphasis ours]

Donnelly notes that many of the victims were found in open spaces
with "no visible marks of fire nearby" and "not a trace of burning upon
their bodies or clothing". Many were found huddled together "in what
were evidently regarded at the moment as the safest places, far away
from buildings, trees, or other inflammable material, and there to have
died together".

One clue, perhaps, is the mention of electrical phenomena:

"Much has been said of the intense heat of the fires which destroyed
Peshtigo, Menekaune, Williamsonville, etc., but all that has been said
can give the stranger but a faint conception of the reality. The heat
has been compared to that engendered by a flame concentrated on an
object by a blow-pipe; but even that would not account for some of the
phenomena. For instance, we have in our possession a copper cent taken
from the pocket of a dead man in the Peshtigo Sugar Bush, which will
illustrate our point. This cent has been partially fused, but still
retains its round form, and the inscription upon it is legible. Others,
in the same pocket, were partially melted, and yet the clothing and the
body of the man were not even singed. We do not know in what way to
account for this, unless, as is asserted by some, the tornado and fire were accompanied by electrical phenomena".

It seems the idea that Mrs. O'Leary's cow triggered the
conflagration in Chicago did not withstand investigation. Speaking of
O'Leary's barn, the fire marshal testified: "We got the fire under
control, and it would not have gone a foot farther; but the next thing
I knew they came and told me that St. Paul's church, about two squares
north, was on fire". They then checked the church-fire, but--"The next
thing I knew the fire was in Bateham's planing-mill".

A writer in the New York "Evening Post" says he saw "buildings far
beyond the line of fire, and in no contact with it, burst into flames
from the interior".

To these references, Donnelly adds a quote from The Annual Record of Science and Industry" for 1876, page 84:

"The flames that consumed a great part of Chicago were of an unusual
character and produced extraordinary effects. They absolutely melted
the hardest building-stone, which had previously been considered
fire-proof. Iron, glass, granite, were fused and run together into
grotesque conglomerates, as if they had been put through a
blast-furnace. No kind of material could stand its breath for a moment."

Another quote from Sheahan & Upton's Work:

"The huge stone and brick structures melted before the fierceness of
the flames as a snow-flake melts and disappears in water, and almost as
quickly. Six-story buildings would take fire and disappear for ever
from sight in five minutes by the watch. . . . The fire also doubled on
its track at the great Union Depot and burned half a mile southward in
the very teeth of the gale--a gale which blew a perfect tornado, and in which no vessel could have lived on the lake. . . . Strange, fantastic fires of blue, red, and green played along the cornices of buildings".

Some additional detail and comments of interest appear in Mel Waskin's more recent book, Mrs. O'Leary's Comet (1985). Speaking of the Peshtigo outburst, he writes -

"Accompanying the firestorm and the wind was a rain of red hot sand.
It was not clear to those eyewitnesses who survived their ordeal where
this sand came from. It must have been raised from the earth by the
incredible winds, but from where? There was sand on the beaches, but
the beaches lay to the east, and the wind was blowing from the west and
the south. There was no sand on the floor of the forest nor on the
farmlands of Wisconsin".

Waskin also mentions incredible "balloons of fire" reported
by many people, including one family that lived between Peshtigo and
Green Bay. "The onslaught was so sudden that the family could only run
to the center of an immense clearing on their farm where nothing
combustible stood. They hoped to be safe, several hundreds yards from
structures or trees.

"When the fire came, rushing on all sides of them, it did not in
fact touch them. But eyewitnesses saw them die. A great balloon of fire
dropped on them - father, mother, and four children. They were
incinerated in an instant. Almost nothing was left of them".

"Many survivors described these great balls of fire falling from the
sky. The whole sky was filled with them; round smoky masses about the
size of a large balloon, traveling at unbelievable speed. They fell to
the ground and burst". Waskin says that a brilliant blaze of fire
erupted from the balloons as they landed, instantly consuming
everything they touched.

Also noteworthy were the reports that the flames erupted from the
basements of the stores when there was "no sign of fire in any other
part of the building". And the basement fires burned with a strange
light, "as if whisky or alcohol were burning".

As something of a footnote to this article, we note a contemporary
report claiming that "The first (and most startling) piece of evidence
is the recent discovery of a 26.5-kilogram carbonaceous chondrite
meteorite on the shores of Lake Huron - 'ground zero' of the astral
bombardment. This report, by Ken Riell, whose claims follow the work of
Donnelly and Waskin, suggests the meteor is of the same composition as
the incoming object in the Tunguska event in Siberia -- 1908.

Also of interest is a presentation on the Peshtigo fire by the
Oconto County Web Project, which discusses the comet hypothesis as a
"plausible" theory -

"Weather historians, using archives as a baseline, and adding
information from recent decades, now offer a plausible theory. Meteor
showers in Autumn are common in the upper great lakes. In recent years
these showers have left burning chunks scattered over the entire
region, some large enough to break through the roofs of homes and out
buildings, starting fires in dry fields and wooded areas. With the
tinder dry conditions present throughout the entire region on the night
of October 8, 1871, such a meteor shower would easily have started what
seemed like spontaneous fires in numerous places of Wisconsin, Michigan
(upper and lower), and Illinois (the Great Chicago Fire). With the
continuous thick smoke from smoldering smaller blazes already
blanketing the land, and the unusually hot weather of that time making
residents seek shelter inside their homes early in the evening, the
meteors that entered the Earth's atmosphere could not easily be seen.
This certainly would account for the sudden eruption of numerous blazes
over the vast area at exactly the same time."

Nevertheless, it is hard to imagine the "cometary" explanation ever
receiving the attention it deserves until those addressing the question
familiarize themselves with the electric comet model. As we have
already emphasized, without this deliberate reconsideration of the
underlying question - what is a comet? - the investigator will either
ignore or forget the most telling clues. In the above reports, for
example, consider the following:

Whirlwind of flame or "perfect tornado"

Tornadoes are a slow electric discharge phenomenon. The ionized
trails of cometary debris, descending through the ionosphere to the
lower atmosphere, produces "lightning conductors" to allow various
forms of "megalightning" to descend to the ground. One of the
manifestations of a powerful direct discharge between the ionosphere
and the Earth could well be a tornado, in which the usual swift
lightning strike is replaced by a slower discharge. Powerful
electromagnetic forces generate a devastating "charge sheath vortex"
that slows the discharge while spreading the devastation on Earth.

Fire descending from the sky

As in the Tunguska event, the appearance of fireballs or
electrically discharging debris, along with associated lightning
manifestations from a clear sky, would be expected as an external body
penetrated Earth's plasma sheath.

Rain of fire and sand

An electrically charged fragment of a comet nucleus will undergo
explosive electrical fragmentation before reaching the Earth's
atmosphere. The electrical model of comets envisions these bodies being
formed by the same processes that created asteroids. Most, if not all,
are as rocky as asteroids. The result of their fragmentation will be a
meteoric shower of granulated silicates, or sand, mixed with flammable
gases and electric discharge phenomena - a 'biblical' rain of fire and
sand.

Descending "balloons" of fire

It is well established that comets discharge carbon compounds that
would be flammable in the Earth's oxygen atmosphere. Gaseous balls of
fire would combine with various weird manifestations of megalightning,
reaching through the meteoric shower of dust to the ionosphere, almost
100 kilometres above the Earth. The spectacle would be beyond normal
experience. In addition, near the Earth, ball lightning could be
expected, given the extreme electrical conditions - and the presence of
ball lightning is surely the plausible explanation for descending
"balloons" with the power to incinerate objects they strike.

Buildings exploding with fire when no fire was yet present

Electrical discharges would take place between metal objects inside
buildings, igniting any flammable materials. The same would hold true
for the hapless man found with melted coins in his pocket but clothes
intact and no other signs of burning. There is, in fact, no other
natural explanation for this enigma.

Colorful flames running along cornices of buildings

This is the usual description of a glow discharge from sharp edges
of rooftops, seen in the midst of powerful electrical storms. It is
called "St. Elmo's fire". The different colors of the flames are due to
the metallic ions sputtered from the surface material.

Fusing of fire-proof building material

Plasma discharges can be used to melt anything. Industrially, plasma torches are used to destroy the most refractory materials.

Basements exploding

"...the basement fires burned with a strange light, "as if whisky or
alcohol were burning". Whisky or alcohol burns with a ghostly blue
light. Similarly, electrical glow discharges from grounded metallic
objects or electrical wiring in the basements of buildings would emit a
flickering, eerie blue light. Any trapped flammable gases formed in the
basements would be ignited by the discharge, resulting in explosions.

-------------------

Our purpose here is not to suggest a definitive answer to the "Great
Conflagration". But the cost of ignoring evidence should be obvious.
The moment one entertains the electrical vantage point, if only to
compare the explanatory power of alternative views, the most
incongruous elements of the story become predictable features. And who could deny that this ability to resolve paradoxes is the mark of a hypothesis that deserves consideration?

Cometary fire ruins, as seen from the corner of Dearborn and Monroe Streets, Chicago, 1871.

Last night we watched Super Comet - After the Impact, a Discovery Channel special that basically takes the comet that wiped out the dinosaursand put into modern times. They added some cheesy drama, following the
struggles of several individuals or groups, before, during, and after
the impact, to show how people would react to such a global cataclysm.
They used the same type of cometary body assumed to have caused the
extinction of the dinosaurs, the same size, same impact location, and
utilized all the computer modeling they have done on this past event to
try to show what might happen (and to show what they think happened
then). Not terribly creative and suggests that they really don't know
all the effects of such an impact and are just putting things together
from what little they have been able to figure out about that one
impact, some (or much) of which may be just speculation, though I'm
sure that there is some good science going on there.

This show highlights what we have already noted in this series of
articles: the difference between the American School of Asteroid
impacts that happen only at millions of years intervals and the British
School which posits that showers of much smaller objects occur with
great frequency in between those millions of years events.

The cheesiest part of this "docu-drama" was, of course, the depicted
foibles of the humans experiencing the event. But, in a way, even those
depictions were useful. The one guy who simply couldn't grasp the
nature of the event, kept traveling "home" (which happened to be the
site of the impact) even when it was clear that there was no home left.
His emotions basically drove him to his own death.

Other people continued to act as if the world was still the same
place and suffered thereby, though they learned to cope. What was
clearly evident was that it was lack of knowledge about such events
that was the chief problem for all of them.

During the course of the show, one of the experts made the remark
"WHEN it happens," as though he - and the rest of them - knew for a
fact that this was on the agenda for our near future. The very fact
that so many scientists are working on these problems, including a
large number of them studying the possible human reactions and
behaviors and how to deal with masses of people, should warn us that
there IS something they aren't telling the masses in the headlines of
our daily newspapers, though certainly they are "testing" public
reactions with shows such as Super Comet - After the Impact.

On my desk, before me, I have a book out of the more than 30 volumes
and scores of papers on the topic of comet and asteroid impacts that I
have collected in the course of this study. The title of this book is Hazards due to Comets and Asteroids edited by Tom Gehrels, with 120 contributing authors, published by the University of Arizona Press in 1994.

There is something in this book that I want to bring to your
attention before we get on to our main catastrophe of the day: Mrs.
O'Leary's Cometary Cow.

The volume mentioned above, Hazards due to Comets and Asteroids,
which we note was published in 1994, (in reaction to the impending
Comet Shoemaker-Levy event vis a vis Jupiter), contains a paper
beginning on page 1225, (yeah, it's a BIG book!), that is written by
Robert L. Park of The American Physical Society, Lori B. Garver of the
National Space Society and Terry Dawson, a staffer for the House
Committee on Science, Technology, and Space working for the Committee's
then Chairman, Rep. George Brown (See him listed HERE). The following is a condensation of the main points of this paper:

Our understanding of the history of Earth and its inhabitants is
undergoing a radical change. The gradual processes of geologic change
and evolution, it is now clear, are punctuated by natural catastrophes
on a colossal scale - catastrophes resulting from collisions of large
asteroids and comets with Earth. It is, to use the popular term, a
"paradigm shift."

This "new catastrophism," is not unlike the revolutions brought
about by the heliocentric solar system of Copernicus, or Darwinian
evolution, or the big bang. In retrospect, such revolutionary ideas
always seem obvious. On reading the Origin of Species, Thomas Huxley
remarked simply: "Why didn't I think of that." Now, looking at the
Moon, we find ourselves wondering why it took so long to ask whether
the process that cratered its surface is still going on. [...]

The long time scale between major impacts has implications for
public policy. Governments do not function on geologic time. On the
North Dakota prairie near the town of Grand Forks, lie the abandoned
ruins of America's ballistic missile defense system. ... Built in
accordance with the ABM treaty, the Grand Forks facility was meant to
defend our retaliatory capacity. It was declared operational in 1975 -
and decommissioned the same year. National leaders had been persuaded
by some scientists that the Grand Forks facility would meet the threat
to our intercontinental ballistic missile fleet, even though other
scientists warned that the system was dangerous and ineffective. It was
closed because the money to operate it was needed for other projects
that were deemed to be more urgent.

The lesson of Grand Forks is as old as human history: societies will
not sustain indefinitely a defense against an infrequent and
unpredictable threat. Governments often respond quickly to a crisis,
but are less well suited to remaining prepared for extended periods.
Even on the brief sacle of human lifetimes, resources are eventually
diverted to more immediate problems, or defenses are allowed to decay
into a state of unreadiness. According to news accounts, in the great
flood of 1993, the U.S. Corp of Engineers prepared to close the massive
iron gates in the vast complex of levees on the Mississippi and its
tributaries only to discover that some of the gates had been removed
and sold for scrap. Periodic inspections had been suspended to save
money. Indeed, civilization will do well to survive long enough to be
threatened by a major asteroid impact; our own destructive impulses of
the unanticipated consequences of our technologies seem likely to do us
in first. It is unrealistic to expect governments to sustain a
commitment to protection against a rare occurrence when they are
constantly under pressure to respond to some perceived immediate crisis.

Particularly now [1994], with nuclear weapons being dismantled by
the major powers, any talk of a nuclear defense against such an
unlikely hazard as cosmic collisions will be seen as an effort by the
weapons community to sustain itself. The risk of diversion of any mitigation system to military uses must be regarded as a more immediate hazard. [...]

Given the frequency of past collisions, major impact is unlikely to occur in the next century. [...]

Discussion of mitigation may serve one public purpose. It is
important that devastation not be accepted as inevitable, otherwise
society might prefer not to know when it is coming. An asteroid
interception workshop hosted by NASA in 1992 concluded that available
technology can deal effectively with a threatening asteroid, given
warning time on the order of several years. That conclusion validates
the view that current efforts should concentrate on detection and orbit
determination.

The challenge of science is to identify objects that threaten Earth
and work out the timetables for their arrival. Here the challenge is
straightforward and technical. [...]

The emphasis has properly been on impacts that would be expected to
have global consequences. Even for objects too small to produce more
than local effects, however, it has been pointed out that an impact
might be misidentified as a nuclear explosion. Misidentification would
be most likely among nations that have recently joined the ranks of
"nuclear powers" and would therefore be expected to have less
sophisticated means of verification.

It is more than a hypothetical concern. We recall that the 1978
South Indian Ocean anomaly, detected by a Vela satellite, was suspected
at the time of being a South African-Israeli nuclear test. In spite of
the failure to find any confirming evidence from intelligence sources
or atmospheric monitoring, it created international tensions that
lasted for years. At the time, there were suggestions that it might
have been an artifact produced by micrometeorite impact on the Vela
satellite itself, but little serious consideration seems to have been
given to the idea that the satellite had observed the fireball from an
asteroid impact in the atmosphere. A 1990 satellite observation of an
apparent asteroid impact fireball over the Western Pacific has been
described by Reynolds (1993). The danger of misidentification, which
grows as weapons proliferate among less sophisticated nations, is
meliorated in part by publicizing the possibility. The only sure means
of avoiding an unfortunate response, however, would be for everyone to
know the impact is coming. Which again places the emphasis on detection.

Efforts to persuade governments to invest significant resources in
evaluation of the hazard of asteroid impacts must overcome what has
been called the "giggle factor." Clearly, elected officials in
Washington are not being inundated with mail from constituents
complaining that a member of their family has just been killed or their
property destroyed by a marauding asteroid. [...]

Congressional involvement has been confined to the Committee on
Science, Space and Technology of the U.S. House of Representatives,
whose current chair, George Brown of California, has maintained an
interest in the asteroid issue for several years. The committee
directed NASA to conduct two international workshops on the asteroid
threat. [...]

In March of 1993, the Space Subcommittee held a formal hearing to
examine the results of the two workshops. Some members remain skeptical
that the threat is real. But even among those who recognize that it is
only a question of when a major impact will occur, there was no sense
of urgency. [...]

The frequency of impacts of objects of various sizes is known only
to limited precisions. In particular, objects up to several meters in
diameter explode in the atmosphere without reaching the surface.
Although the energy released in these explosions may be many times
greater than that released by the Hiroshima bomb, they most frequently
occur over the ocean or sparsely inhabited regions of Earth and go
unreported. [...]

Congress is unlikely to take any action in the absence of public
pressure. Once the public understands that Earth and the life on it
have been shaped by cosmic collisions (and the process is continuing),
they will be more likely to support the science needed to evaluate the
threat. The scientific community must, therefore, concentrate on public
education. [...]

All of this creates a dilemma. While it is important to inform the
public, it is dangerous to encourage fear mongering. ... Scientists
would do well, for example, to avoid such terms as "near miss." The
public understands "near-miss" as the draft of wind from a truck that
passes as you step off the curb - not a truck that went by six hours
earlier. [...]

Even in such staid newspapers as the New York Times and Washington Post,
articles may include a well-reasoned discussion of relative risk, but
the headline writers find "doomsday rock," "space bullets" and "killer
comet" irresistible. These headlines exploit the excessive fear
engendered by events people feel powerless to control. The image of an
indifferent mountain of stone and metal guided by the immutable laws of
physics toward an inevitable rendezvous with Earth, is the stuff of
nightmares. Remarkably, however, Nature has apparently provided a
non-threatening demonstration. The impact of comet Shoemaker-Levy 9 on
the back side of Jupiter in July of 1994 provides an historic
opportunity to educate the public without terrorizing anyone.

Shoemaker-Levy 9, in its last pass by Jupiter, broke into a string
of 21 major pieces. The energy released by the impacts of the full
string will be equivalent to about a billion megatons of TNT. Although
the pieces will impact on the side of Jupiter away from Earth, millions
of amateur astronomers will be watching to see the flashes reflected
from Jupiter's moons. A few hours later, the rotation of Jupiter will
bring the impact region into view. There is great disagreement about
what will be seen, but no one suggests that it will not be spectacular.

The asteroid-comet community needs only to insure that everything is
fully and accurately explained; the message will take care of itself:
(1) the energy deposited by the cosmic impacts is enormous (2) this is
a process that is still going on.

This guy had a lot of faith in human beings, didn't he? He thought
that all scientists had to do was to tell the public the truth and they
would get enough support to fund cataloging the dangerous asteroids in
earth-crossing orbits. He also thought that this was the main problem:
asteroids that could be seen and listed.

What seems obvious to me is that someone else took the "Lesson of
the Grand Forks Facility" in an entirely different way. The question
that comes to my mind is this: are the Elite Powers creating a War On
Terror as an immediate and constant pressure on the public to get the
needed support for the stockpiling of nuclear weapons so they will have
them to use on asteroids? You know, kind of a benevolent lie with a
million or so innocent Iraqis being sacrificed to sustain it. Kind of
like the Madeleine Albright thing: In 1996 then-UN Ambassador Madeleine
Albright was asked by 60 Minutes correspondent Lesley Stahl, in
reference to years of U.S.-led economic sanctions against Iraq, "We
have heard that half a million children have died. I mean, that is more
children than died in Hiroshima. And, you know, is the price worth it?"

To which Ambassador Albright responded, "I think that is a very hard choice, but the price, we think, the price is worth it."

So, is there somebody at the top who thinks that stockpiling nuclear
weapons is a good thing for planetary defense of a cosmic nature?

There is another way to ask the question: are the Powers That Be
using the threat of asteroids on lawmakers to get them to agree to
backing the phony War on Terror in order to obtain and retain the
support of the masses when what they are really doing is just planning
on a fascist take-over of the world? Notice that the paper above also
said:

The risk of diversion of any mitigation system to military uses must be regarded as a more immediate hazard.

It's hard to tell what goes on in the minds of deviants. One thing I
think we can be sure of is that the threat of cometary bombardment is
real and immediate, and that comes from the science. Sadly, it does not
come from our leaders who, even if they are aware of some threat and
are stockpiling nuclear weapons to use to divert inbound asteroids or
comets, haven't bothered to make the threat clear to the masses of
humanity via science as they very well could.

Scanning through this almost 1300 page volume which collects pretty
much all the then scientifically acknowledged data on comet and
asteroid impacts reveals that there was some pretty interesting
thinking going on prior to Shoemaker-Levy 9. We've come a long way in
our understanding since then; well, some have. The U.S. school is still
pretty much stuck in the "single massive asteroid at vast timescales";
probably due to political pressures to keep the real issues covered up.
I noted that Shoemaker had a paper in the volume where he said there
were only 140 known impact craters on the earth. He completely ignored
the Carolina bays which have been reclaimed for what they are by Richard Firestone, Allen West and Simon Warwick-Smith in The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization. I understand that there are over 50,000 of those critters. That's scary!

We also note the remark in the above paper: "The frequency of
impacts of objects of various sizes is known only to limited
precisions. In particular, objects up to several meters in diameter
explode in the atmosphere without reaching the surface." Obviously,
this guy wasn't part of the the same crowd that hung out with Brigadier
General S. Pete Worden, who said that he believes "we should pay more
attention to the 'Tunguska-class' objects - 100 meter or so objects
which can strike up to several times per century with the
destructiveness of a nuclear weapon," reported in the previous article:
Thirty Years of Cults and Comets.

In any event, the authors of the above quoted paper had a generally
open attitude toward the public and educating them that no longer seems
to be the perception of our ruling elites.

Speaking of General Worden and his obscure remark, after publishing
the last installment of the present series, several members of the SOTT Forumdid a little digging on the question and came up with some very
interesting finds. It seems that there were two events in the 1930s
that equalled the Tunguska event:

This article was printed in IMO's December 1995 edition of the WGN
Journal. It was written by Duncan Steel of the Anglo-Australian
Observatory.

There is evidence that there were two massive bolide explosions
which occurred over South America in the 1930's. One seems to have
occurred over Amazonia, near the Brazil-Peru border, on August 13,
1930, whilst the other was over British Guyana on December 11, 1935. It
is noted that these dates coincide with the peaks of the Perseids and
the Geminids, although any association with those meteor showers is
very tentative. The identification of such events is significant in
particular in that they point to the need for re-assessment of the
frequency of tunguska-type atmospheric detonations.

This week marks the golden anniversary of what is arguably the most
spectacular meteorite fall ever seen. At 10:40 a.m. on February 12,
1947, a incredibly bright fireball seared its way across the sky of
eastern Siberia and rained around 70 tons of iron meteorites onto the
rugged landscape. Because it was so well documented, the Sikhote-Alin
fall proved a great boon to meteorite science.

The 1947 Siberian event is considered in most literature as one of
the two most significant events this century where the earth has
encountered objects from space. It was an iron meteorite that broke up
only about 5 miles above the earth. It produced over 100 craters with
the largest being around 85 feet in diameter. The strewnfield covered
an area of about 1 mile by a half mile. There were no fires or similar
destruction like that found at Tunguska. Shredded trees and broken
branches mostly. A total of 23 tons of meteorites were recovered and
it's been estimated it's total mass was around 70 tons when it broke up.

(from Sky Publishing Corporation and George Zay)

There are more, of course, but this just tells us that there are
many things going on here on the Big Blue Marble that we aren't aware
of. That's what Victor Clube is saying in his narrative report to the
USAF and Oxford that sent me off on this topic. So, let's return to
Clube and our historical review:

The next period of cometary activity that Clube refers to is that
which encompassed the American Revolution (1775 - 1783) and the French
Revolution (1789 - 1799) and the mid-nineteenth century crisis. I'm
going to skip the two revolutions for the moment and go directly to the
mid-nineteenth century period because it is intensely interesting and
leads us into our topic of the day.

In trying to find some details about the mid-nineteenth century
crisis mentioned above, a whole lot of things turned up that I'm sure
we all learned in history class in school, but it just never was put
together in a way that made it look as interesting as it does now! What
happened then was, of course, the "Industrial Revolution." But it was
kind of like the Renaissance in that it overlapped a lot of other
interesting events.

The Industrial Revolution and the rise of capitalism began, more or
less, toward the end of the eighteenth century. The nineteenth century
was a turbulent epoch beginning with a stock market crash in 1825 then
moving on to the Panic of 1847, a collapse of British financial markets
associated with the end of the 1840s railroad boom. The crisis of 1847
could have been more disastrous except that it was cut short by
economic revival following the California gold strike of 1849.

After a period of prosperity, there began a series of wars and
revolutions. There was the first Italian War for Independence in 1857,
and then the American Civil War of 1861, the Polish Insurrection of
1863, Napoleon the Second's Mexican adventure and the campaign against
Denmark in 1864 which started the Prussian Wars led by Bismarck.
Bismarck attacked Austria in 1866 and won a victory over France in
1871. The, there was the Republican uprising in Spain which toppled
Queen Isabella from the throne. Finally, there was the last of Louis
Napoleon's adventures which culminated in the crashing of the Empire in
1871.

There was Civil War in France following the downfall of the Second Napoleon, and the people (Paris Communards)
seized power. They were soon crushed and order was restored in the
Third Republic, and the revolutionary tide receded for the rest of the
century.

It is interesting to consider the other events that were occurring
at this time. Industrial capitalism was being spread with missionary
zeal everywhere. Western investors roamed the globe looking for
openings to establish trade and to invest in anything that could be
bought or sold. In the process, millions of people were redistributed
in the greatest mass migrations in history from the Old World to the
New. Science became the handmaiden of industry and capitalism. The
volume of world trade was 1.75 billion dollars in 1830 and it rose to
3.6 billion in 1850, skyrocketing to 9.4 billion in 1870.

So, Clube is right. For about twenty-five years, the entire Western
world was bubbling cauldron of war and revolution and people taking
advantage of wars and revolution to make money. When it was all over,
the imperial powers of Europe that were to rule the world until 1914,
were firmly ensconced. More than that, the United States as a federal,
capitalist entity, had been forged at Appamattox.

There were obviously other things going on at that time. In the
period from 1830 to 1860 there was apparently an enormous upsurge in
religious fervor. The imminent return of Christ was being predicted
everywhere! Manuel de Lacunza, a Catholic priest in South America wrote
(under the pen name of Juan Josafa Ben-Ezra) a book entitled The Coming of Messiah in Glory and Majesty,
which was published in Spain in 1812. He believed that Jesus was coming
very, very soon. William Miller (Seventh-Day Adventists) declared that
Christ was coming and predicted 1844 as the date. Edward Irving of
England and Johann Bengel in Germany almost simultaneously came to the
conclusion that the prophecies of Daniel pointed to the time of the end
being right then; Mason in Scotland, Leonard H. Kelber in Germany and
many, many others preached about the Second coming. Spiritualist Andrew
Jackson Davis gave 157 lectures in 1845 about the new era, which Edgar
Allen Poe attended regularly. The Spiritualism Craze began with the Fox
sisters in 1848. Mourant Brock, of the Church of England, noted that
the craze for eschatology had spread through all of Europe and extended
to India. (See: The Story of Prophecy by Henry James Forman).

As Clube notes, this religious fervor parallels cosmic events.

In 1843, there appeared one of the greatest comets of history. The
Great Comet of 1843 formally designated C/1843 D1 and 1843 I, was
discovered on February 5, 1843 and rapidly brightened. It was a member
of the Kreutz Sungrazers, a family of comets resulting from the breakup
of a parent comet (X/1106 C1) into multiple fragments in about 1106. These comets pass extremely close to the Sun - within a few solar radii - and this is why they often become very bright.

C/1843 D1 moved rapidly toward an incredibly close perihelion of
less than 830,000 km on February 27, 1843, at which time it could be
seen in broad daylight just a degree away from the Sun! It swung around
and passed close to earth on March 6, 1843, and seemed to manifest its
greatest brilliance the following day. It was last observed on April
19, 1843. At that time this comet had passed closer to the sun than any
other known object. The American Journal of Science and The New York Tribune devoted special sections to this comet at the time. You could say that "comet fever" was pandemic!

The Great Comet of 1843 - still unnamed - developed a tail over 2
Astronomical Units in length, the longest known cometary tail until
measurements in 1996 showed that Comet Hyakutake's tail was almost
twice as long.

In 1857, an anonymous German astrologer predicted that a
comet would strike the earth on June 13 of that year. The impending
catastrophe became the talk of all of Europe. The French astronomer,
Jacques Babinet, tried to reassure people by stating that a collision
between the earth and a comet would do no harm. He compared the impact
to "a railway train being hit by a fly". His words, apparently, had
little effect. The Paris correspondent for the American journal, Harper's Weekly, wrote:

Women have miscarried; crops have been neglected; wills have been
made; comet-proof suits of clothing have been invented; a cometary life
insurance company (premiums payable in advance) has been created... all
because an almanac maker... thought proper to insert, under the week
commencing June 13, 'About this time, expect a comet'.

Let's back up just a minute here, to 1826. In 1826, comet 3D/Biela
was discovered by Wilhelm von Biela. It has become known as Comet Biela
or Biela's Comet. This comet had been first seen in 1772 by Charles
Messier and again in 1805 by Jean-Louis Pons. It was von Biela who
discovered it in its 1826 perihelion approach (on February 27) and
calculated its orbit, discovering it to be periodic with a period of
6.6 years which is why it was named after him and not Messier or Pons.
It was only the third comet (at the time) found to be periodic, after
the famous comets Halley and Encke. French astronomer M. Damoiseau
subsequently calculated its path, and announced that on its next return
the comet would cross the orbit of the earth, within twenty thousand
miles of its track, and about one month before the earth would arrive
at the same spot!

When the comet came in 1832, the earth did, indeed, miss it by one
month. It returned again in 1839 and 1846. In its 1846 appearance, the
comet was observed to have broken up into two pieces. It was observed
again in 1852 with the two parts being 1.5 million miles apart. Each
part had a head and tail of its own.

The comet did not come in 1852, 1859, or 1866. The Edinburgh Review notes about this strange state of affairs:

The puzzled astronomers were left in a state of tantalizing
uncertainty as to what had become of it. At the beginning of the year
1866 this feeling of bewilderment gained expression in the Annual
Report of the Council of the Royal Astronomical Society. The matter
continued, nevertheless, in the same state of provoking uncertainty for
another six years. The third period of the perihelion passage had then
passed, and nothing had been seen of the missing luminary. But on the
night of November 27, 1872, night-watchers were startled by a sudden
and a very magnificent display of falling stars or meteors, of which
there had been no previous forecast... [source]

The meteors were radiating from the part of the sky where the comet
had been expected to cross in September. In other words, the trajectory
was the same, and the earth intersected it, but the velocity was
somewhat altered. The American Journal of Science said they
fell like snowflakes. Professor Olmstead, a mathematician at Yale
University estimated 34,640 shooting stars per hour. The New York Journal of Commercewrote that no philosopher or scholar has ever recorded an event like
this. These meteors became known as the Andromedids or "Bielids" and it
seems apparent that they indicated the death of the comet. The meteors
were seen again on subsequent occasions for the rest of the 19th
century, but have now faded away.

Is that all there is to that?

Maybe not.

As it happens, on Sunday, the 8th of October, in the year 1871, at
half past nine o'clock in the evening, events occurred which caused the
death of hundreds of human beings, and the destruction of vast amounts
of property, across three different States of the American Union,
sending millions of people into fits of the wildest alarm and terror.
The following passages are extracted from the History of the Great Conflagration, Sheahan & Upton, Chicago 1871. [source]

The summer of 1871 had been excessively dry; the moisture seemed to
be evaporated out of the air; and on the Sunday above named the
atmospheric conditions all through the Northwest were of the most
peculiar character. The writer was living at the time in Minnesota,
hundreds of miles from the scene of the disasters, and he can never
forget the condition of things. There was a parched, combustible,
inflammable, furnace-like feeling in the air, that was really alarming.
It felt as if there were needed but a match, a spark, to cause a
world-wide explosion. It was weird and unnatural. I have never seen nor
felt anything like it before or since. Those who experienced it will
bear me out in these statements.

At that hour, half past nine o'clock in the evening, at apparently
the same moment, at points hundreds of miles apart, in three different
States, Wisconsin, Michigan, and Illinois, fires of the most peculiar
and devastating kind broke out, so far as we know, by spontaneous
combustion.

In Wisconsin, on its eastern borders, in a heavily timbered country,
near Lake Michigan, a region embracing four hundred square miles,
extending north from Brown County, and containing Peshtigo, Manistee,
Holland, and numerous villages on the shores of Green Bay, was swept
bare by an absolute whirlwind of flame. There were seven hundred and
fifty people killed outright, besides great numbers of the wounded,
maimed, and burned, who died afterward. More than three million
dollars' worth of property was destroyed. (pp 393, 394, etc.)

"At sundown there was a lull in the wind and comparative stillness.
For two hours there were no signs of danger; but at a few minutes after
nine o'clock, and by a singular coincidence, precisely the time at
which the Chicago fire commenced, the people of the village heard a
terrible roar. It was that of a tornado, crushing through the forests.
Instantly the heavens were illuminated with a terrible glare. The sky,
which had been so dark a moment before, burst into clouds of flame.

A spectator of the terrible scene says the fire did not come upon
them gradually from burning trees and other objects to the windward,
but the first notice they had of it was a whirlwind of flame in great
clouds from above the tops of the trees, which fell upon and entirely
enveloped everything. The poor people inhaled it, or the intensely hot
air, and fell down dead. This is verified by the appearance of many of
the corpses. They were found dead in the roads and open spaces, where
there were no visible marks of fire near by, with not a trace of
burning upon their bodies or clothing. At the Sugar Bush, which is an
extended clearing, in some places four miles in width, corpses were
found in the open road, between fences only slightly burned. No mark of
fire was upon them; they lay there as if asleep. This phenomenon seems
to explain the fact that so many were killed in compact masses. They
seemed to have huddled together, in what were evidently regarded at the
moment the safest places, far away from buildings, trees, or other
inflammable material, and there to have died together. (p. 372)

Another spectator says:

"Much has been said of the intense heat of the fires which destroyed
Peshtigo, Menekaune, Williamsonville, etc., but all that has been said
can give the stranger but a faint conception of the reality. The heat
has been compared to that engendered by a flame concentrated on an
object by a blow-pipe; but even that would not account for some of the
phenomena. For instance, we have in our possession a copper cent taken
from the pocket of a dead man in the Peshtigo Sugar Bush, which will
illustrate our point. This cent has been partially fused, but still
retains its round form, and the inscription upon it is legible. Others,
in the same pocket, were partially melted, and yet the clothing and the
body of the man were not even singed. We do not know in what way to
account for this, unless, as is asserted by some, the tornado and fire
were accompanied by electrical phenomena" (373).

"It is the universal testimony that the prevailing idea among the
people was, that the last day had come. Accustomed as they were to
fire, nothing like this had ever been known. They could give no other
interpretation to this ominous roar, this bursting of the sky with
flame, and this dropping down of fire out of the very heavens,
consuming instantly everything it touched.

"No two give a like description of the great tornado as it smote and
devoured the village. It seemed as if 'the fiery fiends of hell had
been loosened,' says one. 'It came in great sheeted flames from
heaven,' says another. 'There was a pitiless rain of fire and *sand*.'
'The atmosphere was all afire.' Some speak of 'great balls of fire
unrolling and shooting forth in streams.' The fire leaped over roofs
and trees, and ignited whole streets at once. No one could stand before
the blast. It was a race with death, above, behind, and before them"
(Ibid 374).

A civil engineer, doing business in Peshtigo, says:

"The heat increased so rapidly, as things got well afire, that, when
about four hundred feet from the bridge and the nearest building, I was
obliged to lie down behind a log that was aground in about two feet of
water, and by going under water now and then, and holding my head close
to the water behind the log, I managed to breathe. There were a dozen
others behind the same log. If I had succeeded in crossing the river
and gone among the buildings on the other side, probably I should have
been lost, as many were."

In Michigan, one Allison Weaver, near Port Huron, determined to
remain, to protect, if possible, some mill-property of which he had
charge. He knew the fire was coming, and dug himself a shallow well or
pit, made a thick plank cover to place over it, and thus prepared to
bide the conflagration. I quote:

"He filled it nearly full of water, and took care to saturate the
ground around it for a distance of several rods. Going to the mill, he
dragged out a four-inch plank, sawed it in two, and saw that the parts
tightly covered the mouth of the little well. 'I calculated it would be
touch and go,' said he, 'but it was the best I could do.' At midnight
he had everything arranged, and the roaring then was awful to hear. The
clearing was ten to twelve acres in extent, and Weaver says that, for
two hours before the fire reached him, there was a constant flight
across the ground of small animals. As he rested a moment from giving
the house another wetting down, a horse dashed into the opening at full
speed and made for the house. Weaver could see him tremble and shake
with excitement and terror, and felt a pity for him. After a moment,
the animal gave utterance to a snort of dismay, ran two or three times
around the house, and then shot off into the woods like a rocket."

"Not long after this the fire came. Weaver stood by his well, ready
for the emergency, yet curious to see the breaking-in of the flames.
The roaring increased in volume, the air became oppressive, a cloud of
dust and cinders came showering down, and he could see the flame
through the trees. It did not run along the ground, or leap from tree
to tree, but it came on like a tornado, a sheet of flame reaching from
the earth to the tops of the trees. As it struck the clearing he jumped
into his well, and closed over the planks. He could no longer see, but
he could hear. He says that the flames made no halt whatever, or ceased
their roaring for an instant, but he hardly got the opening closed
before the house and mill were burning tinder, and both were down in
five minutes. The smoke came down upon him powerfully, and his den was
so hot he could hardly breathe.

"He knew that the planks above him were on fire, but, remembering
their thickness, he waited till the roaring of the flames had died
away, and then with his head and hands turned them over and put our the
fire by dashing up water with his hands. Although it was a cold night,
and the water had at first chilled him, the heat gradually warmed him
up until he felt quite comfortable. He remained in his den until
daylight, frequently turning over the planks and putting out the fire,
and then the worst had passed. The earth around was on fire in spots,
house and mill were gone, leaves, brush, and logs were swept clean away
as if shaved off and swept with a broom, and nothing but soot and ashes
were to be seen" (390).

In Wisconsin, at Williamson's Mills, there was a large but
shallow well on the premises belonging to a Mr. Boorman. The people,
when cut off by the flames and wild with terror, and thinking they
would find safety in the water, leaped into this well.

"The relentless fury of the flames drove them pell-mell into the
pit, to struggle with each other and die - some by drowning, and others
by fire and suffocation. None escaped. Thirty-two bodies were found
there. They were in every imaginable position; but the contortions of
their limbs and the agonizing expressions of their faces told the awful
tale". (386)

James B. Clark, of Detroit, who was at Uniontown, Wisconsin, writes:

"The fire suddenly made a rush, like the flash of a train of
gunpowder, and swept in the shape of a crescent around the settlement.
It is almost impossible to conceive the frightful rapidity of the
advance of the flames. The rushing fire seemed to eat up and annihilate
the trees."

They saw a black mass coming toward them from the wall of flame:

"It was a stampede of cattle and horses thundering toward us,
bellowing, moaning, and neighing as they galloped on; rushing with
fearful speed, their eyeballs dilated and glaring with terror, and
every motion betokening delirium of fright. Some had been badly burned,
and must have plunged through a long space of flame in the desperate
effort to escape.

Following considerably behind came a solitary horse, panting and
snorting and nearly exhausted. He was saddled and bridled, and, as we
first thought, had a bag lashed to his back. As he came up we were
startled at the sight of a young lad lying fallen over the animal's
neck, the bridle wound around his hands, and the mane being clinched by
the fingers. Little effort was needed to stop the jaded horse, and at
once release the helpless boy. He was taken into the house, and all
that we could do was done; but he had inhaled the smoke, and was
seemingly dying. Some time elapsed and he revived enough to speak. He
told his name - Patrick Byrnes - and said: 'Father and mother and the
children got into the wagon. I don't know what became of them.
Everything is burned up. I am dying. Oh! Is hell any worse than this?'"
(383)

When we leave Wisconsin and pass about two hundred and fifty
miles eastward, over Lake Michigan and across the whole width of the
State of Michigan, we find much the same condition of things, but not
so terrible in the loss of life. Fully fifteen thousand people were
rendered homeless by the fires; and their food, clothing, crops,
horses, and cattle were destroyed. Of these five to six thousand were
burned out the same night that the fires broke out in Chicago and
Wisconsin. The total destruction of property exceeded one million
dollars; not only villages and cities, but whole townships, were swept
bare.

But it is to Chicago we must turn for the most extraordinary
results of this atmospheric disturbance. It is needless to tell the
story in detail. The world knows it by heart. I have only space to
refer to one or two points,

The fire was spontaneous. The story of Mrs. O'Leary's cow having
started the conflagration by kicking over a lantern was proved to be
false. It was the access of gas from the tail of Biela's comet that
burned up Chicago!

The fire-marshal testified: "I felt it in my bones that we were going to have a burn." He says, speaking of O'Leary's barn:

"We got the fire under control, and it would not have gone farther;
but the next thing I knew they came and told me that St. Paul's church,
about two squares north, was on fire". (163)

They checked the church-fire, but - "The next thing I knew the fire was in Bateham's planing-mill."

A writer in the New York Evening Post says he saw in Chicago "buildings far beyond the line of fire, and in no contact with it, burst into flames from the interior."

It must not be forgotten that the fall of 1871 was marked by
extraordinary conflagrations in regions widely separated. On the 8th of
October, the same day the Wisconsin, Michigan, and Chicago fires broke
out, the States of Iowa, Minnesota, Indiana, and Illinois were severely
devastated by prairie-fires; while terrible fires raged on the
Alleghenies, the Sierras of the Pacific coast, and the Rocky Mountains,
and in the region of the Red River of the North.

The Annual Record of Science and Industry for 1876, page 84, says:

"For weeks before and after the great fire in Chicago in 1872, great
areas of forest and prairie-land, both in the United States and the
British Provinces, were on fire."

The flames that consumed a great part of Chicago were of an unusual
character and produced extraordinary effects. They absolutely melted
the hardest building-stone, which had previously been considered
fire-proof. Iron, glass, granite, were fused and run together into
grotesque conglomerates, as if they had been put through a
blast-furnace. No kind of material could stand its breath for a moment.

I quote again from Sheahan & Upton's work:

"The huge stone and brick structures melted before the fierceness of
the flames as a snow-flake melts and disappears in water, and almost as
quickly. Six-story buildings would take fire and disappear for ever
from sight in five minutes by the watch... The fire also doubled on its
track at the great Union Depot and burned half a mile southward in the
very teeth of the gale - a gale which blew a perfect tornado, and in
which no vessel could have lived on the lake... Strange, fantastic
fires of blue, red, and green played along the cornices of buildings"
["History of the

Chicago Fire" 85, 86].

Hon. William B. Ogden wrote at the time:

"The fire was accompanied by the fiercest tornado of wind ever known to blow here" [Ibid 87].

"The most striking peculiarity of the fire was its intense heat.
Nothing exposed to it escaped. Amid the hundreds of acres left bare
there is not to be found a piece of wood of any description, and,
unlike most fires, it left nothing half burned... The fire swept the
streets of all the ordinary dust and rubbish, consuming it instantly"
[Ibid 119].

The Athens marble burned like coal!

"The intensity of the heat may be judged, and the thorough
combustion of everything wooden may be understood, when we state that
in the yard of one of the large agricultural-implement factories was
stacked some hundreds of tons of pig-iron. This iron was two hundred
feet from any building. To the south of it was the river, one hundred
and fifty feet wide. No large building but the factory was in the
immediate vicinity of the fire. Yet, so great was the heat, that this
pile of iron melted and run, and is now in one large and nearly solid
mass" [Ibid 121].

The amount of property destroyed was estimated by Mayor Medill
at one hundred and fifty million dollars; and the number of people
rendered houseless, at one hundred and twenty-five thousand. Several
hundred lives were lost.

"What eyewitnesses described was more like a holocaust from heaven
than an accidental fire started by a nervous cow. And in fact, according
to a theory propounded by Minnesota Congressmen Ignatius Donnelly, the
devastating fires of 1871 did fall from above, in the form of a wayward
cometary tail. During it's 1846 passage, Biela's comet had
inexplicably split in two; it was supposed to return in 1866, but
failed to appear. Biela's fragmented head finally showed up in 1872 as
a meteor shower.

"Donnelly suggested the separated tail appeared in 1871 and was the
prime cause of the widespread firestorm that swept the Midwest,
damaging or destroying a total of twenty-four towns and leaving 2,000
or more dead in its wake. Drought conditions that fall no doubt
contributed to the extent of the conflagration.

"History today concentrates on the Chicago Fire alone and largely
overlooks the Peshtigo Horror, as it was then called. It ignores
altogether Biela's comet and it's unaccounted-for tail. (Ken Rieli)

No doubt that this story came to the attention of Victor Clube!

Ten years later, there was the Great Comet of 1881 (C/1881 K1),
discovered by the Australian amateur astronomer, John Tebbutt. All we
hear about this comet nowadays is that it was one of the first comets
photographed and studied scientifically. However, this comet following
so closely on the events of ten years previously obviously got a few
people thinking.

Ignatius Donnelly, who had already stated that he thought the Great Chicago Fire had been caused by cometary debris, published a book in 1882, entitled Ragnarok,
wherein he proposed that a giant comet had passed close to the earth in
past ages. The intense heat from the comet had set off huge fires that
raged across the face of the globe. He suggested that the comet had
dumped vast amounts of dust on the earth, triggered earthquakes,
leveled mountains, and initiated the ice age. He even explained some of
the miracles of the Bible in terms of his comet, proposing that the
standing-still of the sun at the command of Joshua was possibly a tale
commemorating this event. Donnelly's readers were thrilled by his
descriptions of the "glaring and burning monster" in the sky, scorching
the planet with unearthly heat and shaking the land with "thunders
beyond all thunders".

Possibly inspired by Donnelly (not to mention what was obviously going on in the heavens), Camille Flammarion wrote The End of the Worldin 1893 in which he recounted a fictional collision between the earth
and a comet fifty times its size. Flammarion's lurid prose ensured that
his book was an immediate sensation! (Flammarion, it should be noted,
was a friend and associate of, and greatly influenced by, Allan Kardec,
the French Pedagogue, medical student, linguist and researcher of
"spirit communications." He was also a friend of Jules Violle the
probable true identity of the legendary alchemist, Fulcanelli.)

Well, all that was a pretty interesting diversion into history, now
wasn't it? Doesn't seem quite so dull and boring anymore, eh? Okay,
time to return to Victor Clube's narrative. I think that what he is
writing will make a whole lot more sense now!

The fact of a perceived danger at these epochs, signified
historically by a global rise in eschatological concern, is now
understood in various academic quarters as marking some kind of
physical dislocation (climate? disease?) which causes economic and
social activity to be widely deranged, even to the point of collapse of
civilized society, leading then to revolution, mass migration and war,
amplified on a global scale. The occasions of such breakdowns in
civilization are of course a matter of serious concern and their
systematic study has been taken up in America (and elsewhere) at such
institutes as the Center for Comparative Research in History, Society
and Culture at the University of California, Davis (Goldstone, 1991).
To the "enlightened" however, the eschatology remains an anomaly and
secure connections with celestial inputs have generally still to be
made. We should recall however that many, as usual on these occasions
of breakdown, would see "blazing stars threatening the world with
famine, plague and war; to princes' death; to kingdoms many curses;
[and] to all estates many losses..."

The three earliest of these epochs are of course the periods of
Inquisition and of the great European witch-hunts (which spilled over
to America) when ecclesiastical and secular administrators alike would
discourage any (astrological) notion that the celestial sphere
interfered with terrestrial affairs. The separate stories of scientific
revolutionaries like Copernicus, Kepler, Bruno, Galileo and Newton now
bear witness to the ferocity with which the most acceptable cosmic
viewpoint (of the time) was imposed. Indeed, these separate stories are
still being adjusted and Newton, it is now realised, was constrained by
his times to work under conditions of rather considerable censorship.

The acceptable part of his scientific output was of course published
and has proved its worth repeatedly over 300 years. The unacceptable
part however dealt with "blazing stars" and eschatology and remained
unpublished for some 250 years. One of the first to examine this
material (Keynes 1947) was so taken aback by the contrast as to dub
Newton not so much "the first of the age of reason" as "the last of the
magicians, the last of the Babylonians and Sumerias". Thus it was the
Founding Fathers of the Royal Society in Restoration England who hit
upon the "enlightened" step of deriding the cosmic threat and public
anxiety; and it is not without significance today that English-speaking
nations ultimately stood firm and prospered as others faltered at the
last and briefest of the above epochs (Goldstone, loc cit).
Accordingly, it is largely an Anglo-Saxon "achievement" that cosmic
catastrophes were absolutely discarded and the scientific principle of
uniformitarianism was put in place between 200 and 150 years ago.

If short-period bombardment of our planet by comets or comet dust is
a reality (as it increasingly appears to be); and the effects of such
an event are deleterious in the extreme; and if we are in fact overdue
for a repeat performance of such a visitation (which also appears to be
the case); what effect might public awareness of this have on the
status quo on the planet at present? Would the bogus "war on terror"
not become instantly obsolete and would people across the planet not
immediately demand that their political leaders reassess priorities and
take whatever action possible to mitigate the threat? And if those
political leaders refused to do so and it became known that that this
grave threat to the lives of billions was long-standing and common
knowledge among the political elite (with all that that implies), what
then? Revolution? One last hurrah before the 6th extinction?

Who knows. We only know that this knowledge, in its fullest
explication, is being suppressed and marginalized. The reasons for the
psychological games and ploys may be interesting to investigate. so
that is what we will look at next: Why is Humanity so Deaf, Dumb and
Blind?

Last night several witnesses reported to the program Última Hora
that a "UFO" that fell at 4:00 am behind Las Ánimas Hill could have
been the cause of the enormous and devastating fire that affected
hundreds of hectares.

"It was like a huge fire ball that fell behind the hill", said a neighbor, whose report was confirmed by others.

A Ronicevi metallurgic worker, whose shift began at 4:00 am, said
that the UFO gave off an intense glow and its size was similar to the
moon in its full phase.

As of midnight last night, the authorities had neither confirmed the
origin of the fires nor found the remains of the object that was seen
by the neighbors.

Nevertheless, official sources stated that last Monday's fire was
caused by the re-ignition of the previous day's fire, which was
initially reported to be under control.

A smack from a small comet in the 1980s may be responsible for
ripples in one of Saturn's rings, images from NASA's Cassini spacecraft
suggest. The finding is another indication that the rings are not
static and can change on human timescales.

Cassini observations have revealed bright and dark bands in Saturn's
innermost ring, called the D ring. The bands are getting more closely
spaced as time goes on - Hubble Space Telescope images reveal they were
60 kilometres apart in 1995 and Cassini shows they have been shrinking
over the last few years and are just 30 km apart now.

The
edge of the D ring is seen at the centre of this image, showing a
banded structure that has gradually became more finely spaced since it
was first detected by Hubble in 1995

The Cassini observations suggest that the D ring is not perfectly
flat but has small vertical hills and valleys, like grooves in a
record. The deviations from perfect flatness are just a kilometre in
height, while the ring itself is about 140,000 kilometres across.

Sunlight reflected from these ripples is thought to create bright
bands where it hits a relatively large amount of material and dark
bands where it hits a smaller amount (see illustration).

The gradual narrowing of the bands has been a puzzle to Cassini
scientists, but a new analysis suggests it is the result of an object,
perhaps a very small comet, hitting the rings in the 1980s.

Cascade of collisions

Researchers led by Matthew Hedman of Cornell University in Ithaca,
New York, US, modelled what would happen if a body a few metres across
and travelling at a few dozen kilometres per second struck one of the
icy chunks that makes up the D ring.

"They would both shatter and send a plume of material into the
rings," Hedman says. The fragments from this collision would in turn
collide with other particles in the ring, creating a cascade of
collisions. After all of these collisions, the ring would end up tilted
with respect to Saturn's equator.

This configuration is unstable, however. A computer model developed
by the team shows that Saturn's gravity starts twisting and deforming
the tilted ring, creating a rippled spiral. As time goes on, this
spiral winds up tighter and tighter until it looks like a grooved
record, just as the D ring appears today.

Using the model, the team calculated that the collision would have
needed to occur in 1984 to reproduce the ring's appearance today. "This
is just further evidence showing that these rings really are dynamic
objects," Hedman says. "They're not eternal structures."

Hedman presented the results at a meeting of the American
Astronomical Society's Division for Planetary Sciences in Pasadena,
California, US.

Yesterday, newly discovered asteroid 2008 CT1 flew past Earth only
72,000 miles (0.3 lunar distances) away. Had it struck our planet, the
13-meter wide space rock (similar in size to a school bus) would have
done little damage, probably exploding in the atmosphere and peppering
some lonely stretch of ocean with meteorites. Maybe next time...

Denton County sheriff's dispatchers received nine calls from
residents between 11:45 and 11:51 p.m. asking whether the shaking was
an earthquake, a sonic boom, an explosion or something else altogether.

The earth moved Tuesday night for many Denton-area residents, but what caused it remains a mystery.

"I was laying in bed, reading a book when it happened. It seemed
like a loud noise and the whole house shook for a second or two," said
Susan Seaborn of Corinth.

She looked at her watch when the windows rattled. It read 11:34 p.m.

"But my husband said, 'I don't remember a bang.'"

Seaborn said she felt another bump a few minutes later, although her husband said he didn't feel that either.

The couple looked around their house and found no damage, but they
did find their neighbors outside doing the same thing. Their neighbors
thought a tree had fallen on their roof.

Denton County sheriff's dispatchers received nine calls from
residents between 11:45 and 11:51 p.m. asking whether the shaking was
an earthquake, a sonic boom, an explosion or something else altogether.

University of Texas professor Cliff Frohlich, an expert on Texas
earthquakes, said that he, too, received calls from Denton-area
residents curious whether what they felt was an earthquake.

There were no reports from the National Earthquake Information
Center, but that seismic data is limited to quakes that register
magnitude 3 or more on the Richter scale, Frohlich said.

"And that would be felt across the state," Frohlich said.

A seismograph in Hockley, north of Houston, showed no activity
either, but a small tremor, measuring 2 or less on the Richter scale,
would be felt only locally. Such a quake could be measured only if
there were instruments in the area, he said.

The most recent measurable earthquake in North Texas shook Commerce
on May 13, 1997, with a 2.9 magnitude temblor. The nearest quake shook
Valley View on Sept. 18, 1985, measuring 3.3 on the Richter scale. The
biggest quake in North Texas was centered just north of Paris and
measured 4.2 back in 1934, Frohlich said.

The biggest quakes on record in the nation's midsection occurred in
Missouri in 1811 and 1812. Based on damage reports, experts estimate
those quakes measured about 8 on the Richter scale.

The kinds of reports people have made about Monday night's shake are consistent with a temblor of 2 or less, Frohlich said.

"People report a loud noise or a jolt. They hear them more than they feel them," Frohlich said.

But, he said, the reports are also consistent with other earth-shaking events, such as storms and sonic booms.

Jody Gonzalez, Denton County emergency management coordinator, said
that the southwestern corner of the county is in a Fort Worth-Wichita
Falls flight path where pilots are allowed to fly their craft at
supersonic speeds.

If an airplane does pass the speed-of-sound barrier, the boom could
be felt anywhere in the county, depending on the wind, Gonzalez said.
But emergency management officials aren't typically told when such a
flight has come through.

Polk County, FL -- A Polk County man videotapes a strange fireball
in the sky over Polk County. Rhett Marcotes and his family saw the
phenomenon on January 7th just before dusk outside his home in
Davenport. Marcotes and his wife grabbed their video camera and began
filming. The results were stunning.

Marcotes says they couldn't figure out what it was. The filmed it
for about nine minutes until it passed the tree line. They showed the
tape to co-workers, friends, and family. Marcotes says everyone has a
theory to the fireball over Polk County. Some said space junk, others
said meteors, and some even said it was aliens.

Marcotes and his family weren't the only ones to see the fireball.
Several people called 9-1-1 in Polk County to report the fire in the
sky. The sheriff's office provided us copies of the tapes and you can
hear them here.

We took the tape to two professors at Florida Southern College in
Lakeland. That's about 30 miles from where Marcotes saw the fireball.
Doctors Mossayeb Jamshid and Peter Bias say they don't believe the
video shows a celestial event. They say the contrail and brightness
suggest jets or engines of some sort enormously high in the atmosphere.

We also showed a copy to Stephen Nipper. He's the Manager of
Planetarium and Senior Programs at the Museum of Science and Industry
in Tampa.

Steve Nipper- Museum of Science and Industry:

"This video is a good example of how an ordinary object, under
slightly unusual viewing conditions can present a spectacular visual
(and video) image. It is definitely a condensation trail, or contrail,
from a jet aircraft. There were no re-entries of space debris on that
day, and no reports which

I could find in the scientific or aeronautical communities of a significant meteor entry. "

"In addition, at around 6 minutes into the video, there is a second,
fainter and lower, but similar object crossing the field of view
perpendicular to the path of the first object.

Also, the duration of the sighting indicates that the object was
moving at a slow speed in comparison to a meteor or orbiting space
debris. The speed at which the object crossed the sky is very typical
of a high flying jet."

"The combination of upper atmosphere conditions which produced
contrails which rapidly evaporated, along with a low angle of the Sun
and the smoke in the air from the fire which got out of control, lit
the contrail brightly and reddened it significantly."

Callers from Oak Island, Leland and Supply told the Star-Newsthey heard the booms and felt strong vibrations. One man said he
thought his beach-front home was collapsing. Another said it shook her
whole house.

A meteorologist at the National Weather Service office in Wilmington
said reports of the booms or vibrations were widespread, coming from
Rocky Point in Pender County to Leland in Brunswick County.

The Brunswick County 911 center's switchboard lit up with calls from people reporting explosions or loud booms.

A dispatcher said the center had not confirmed the source of the loud noises.

Although a dispatcher at the New Hanover County 911 center said the center had received no such calls, a Star-News staffer who lives in the Sunset Park neighborhood of Wilmington said he heard the noise at his home.

Mysterious booms known as "Seneca Guns" have been reported in the
region for centuries. The name comes from a similar phenomenon in New
York and Connecticut.

Legend has it that the Seneca Indians are getting their revenge with the guns that Europeans used to displace them.

More scientific explanations say the boom of the guns comes from
earthquakes, material falling off the continental shelf, or pockets of
hot air exploding like balloons.

"We have no idea what it was," said Michael Ross, the meteorologist
at the weather service in Wilmington. "We felt the building kind of
shake for just a split second."

Ross said staff at the NWS office was keeping tabs on the National
Earthquake Center to see if there was a report of an earthquake in the
region, but none was reported.

Ross said he wasn't aware of any military maneuvers off the coast,
which occasionally is spotted on NWS radar when aircraft drop material
to confuse enemy radar systems.

Calls to the public information office at Cherry Point Marine Corps Air Station in Havelock were not answered.

Moderator: In introduction, I just should say that Victor is the author of two extremely intriguing books. The first is The Cosmic Serpent which was published in 1982, and the second is The Cosmic Winter,
published in 1990 in collaboration with astronomer Bill Napier. And I
think that today Victor is going to present a talk illustrated by
slides which will continue along the lines that he developed in The Cosmic Winter, which is a book that I urge all of you to read if you can.

Victor Clube.

What I propose to do this morning is kind of take advantage of the
few things I talked about last night, and go on from there. But there
was a slight hitch with the overlay, which got chopped in half, and I
thought as a result of some of the comments that were made I would kick
off with a few slides, straight away this morning to, perhaps, just
give you a little more of a feel for the things that I'm talking about.

I actually take a little time to gravitate in the community that I'm
not familiar with, and I do realize that the need to talk of
catastrophism in terms of planets kind of takes you away from the
starting point which I perceive to be more important; namely, the
smaller bodies, the meteors, the meteoroids, which I talk about. And I
thought, perhaps, therefore, a few illustrations might just put you in
a slightly better frame of mind for receiving what I'm talking about.
So if I may have the slides, please. Indeed, I can't really claim much
for any of these pictures, but this is an illustration of the zodiacal
cloud.

This is the disk of dust in the inner solar system which, if you're
in a good observing site you may be fortunate enough to see. I come
from England. We never see it, so it's rather a dramatic thing to show
a picture where you actually can see this cloud projecting away from
the Sun, below the horizon, into the plane of the ecliptic.

That dust is cometary and partially asteroidal material. It is a
decay product built up by comets over longish periods of time in the
inner solar system. Next slide please.

This is familiar to you all. This is just a meteor shower. The
objects producing these meteors are typically a gram or so, maybe a
tenth of a gram, maybe ten grams. These are breaking up, or burning up,
at high altitude in the atmosphere 100 kilometers, and they are not
dangerous.

That picture I showed you a bit of yesterday, and this is really
just the painting illustrating that some people, in the past at least,
perceived something looking like meteors as being capable of causing
damage; indeed sufficient damage to be described as "the end of the
world." And to some extent part of our problem in modern science is
whether we should believe this kind of version of history.

We do know that large meteoroids, ones as large as 10E11, 10E12
grams, or larger - that's the mass of the Tunguska object - so anything
which I would call Tunguska or super Tunguska is capable of producing
this kind of damage. It's usually things that explode above the level
of the ground, maybe five or six kilometers in the air. They are
smaller than comets. And on the whole, we can't see any of them.
They're out there. There are telescopes now detecting such sized
objects, but really it's not an active, ongoing business.

Much of my talk is actually about meteoroids between Tunguskas and
meteors. And they're objects with masses of the order 10E6, 10E8, 10E10
grams. These are the objects which produce what I call fireballs in the
atmosphere, and I showed you that the Chinese were recording these
large meteoroids, fireballs, down the centuries, and it was they that
dramatically changed in numbers as the years went by. You must not get
the impression that we in Europe were unaware of fireballs.

The fact is, we just didn't have an organized observatory, anywhere,
doing the job, so we weren't really quite as an advanced civilization
as the Chinese. Nevertheless, people in the seventeenth/sixteenth
century were trying to come to terms with the phenomenon they obviously
observed. And this is merely a theoretical picture, if you like,
illustrating what a fireball was.

Here are the frightened folks down below. There are the fireballs
coming down. And there is the source - some kind of clash in the sky;
slightly more modern than gods fighting each other, armies shooting
each other and the fireballs a stray shot, if you like. Well, some
theory, but at least somebody is clearly thinking about it.

This is back to front, but it doesn't matter, it'll serve. This is
actually a satellite. I forget its name (Geos II, or something like
that), which was measuring dust particles out of the atmosphere above
the Earth, well into space, and some twenty/thirty years ago. And it
was one of the experiments that began to give us a little more insight
into what was around out there. None of this we could see.

This satellite was fitted with dust fences and it went up to check
if the zodiacal cloud was there, as we saw it. And the interesting
thing was that the prediction, from what we observed, roughly turned
out to be right. And it's that heap of particles of a certain size, up
to about a hundred microns. We're looking at the larger particles on
the right. And that sort of normal shape and histogram is, in fact, the
expected zodiacal cloud particles which this satellite was meant to
measure.

The surprise in the experiment was that there were a lot more dust
particles, of smaller size, in fact occurring with time intervals
between them which were very small. And the number of dust particles
which you see there is actually comparable in size to the number in the
zodiacal cloud. These dust particles could only be understood as being
the fragmentation products of larger objects, the debris of which the
satellite was passing through.

What we discovered, in fact, from this experiment was that
meteoroids, the objects that produce fireballs, were also breaking up
at a very high level above the Earth. And there were objects of masses
like 102 through to a million grams. They would, if they could hold
together, produce fireballs at a low level.

But, because they are so weakly constituted they break up at very
high level and produce, really, micron/submicron dust that then floats
down through the atmosphere, undetected. So the message I want to give
you is that it's not all zodiacal dust that's making up the material
that arrives in the atmosphere. It's actually breaking up from
meteoroids.

Much of my talk this morning will relate to what I mentioned
yesterday-a thing called the Taurid meteor stream, and, again, I want
you to know that the Taurid meteoroid stream is not something that we,
as it were, learned about fifty or sixty years ago from meteors and
we've simply been checking that result ever since.

The remarkable thing about the space age is that it has actually
revealed more and more things in the Taurid meteor stream which is
actually built up from interpretations of all these modern observations
that were simply not available at the time, for example, when
Velikovsky was writing Worlds in Collision.

So, essentially, what I'm describing to you is a scientific story
based upon the very latest evidence from space. And this is merely
illustrating one example of the kind of surprises that came our way.

The Apollo astronauts planted seismometers on the Moon, primarily to
measure Moonquakes. But they got diverted from their business by the
discovery that objects, which they didn't expect at least, were hitting
the Moon. These seismometers regularly recorded large bodies hitting
the Moon like the meteoroids which I've just been describing. And this
diagram is an illustration of the record of the incidence of these
meteoroids, integrated over a period of about seven years until NASA
switched the machine off- in exasperation, apparently, because they
didn't think it was telling us anything very interesting.

Nevertheless, for seven or eight years they accumulated this data,
and what you see here is the integral result of the observations, per
day, through the years, throughout the whole of this seven or eight
year period. And, of course, it looks a little like the skyline of
Oxford, where I come from, but never mind, the prominent thing is that
you see one remarkable peak in the middle which is, in fact, centered
on about the 30th June. And all that peak, in fact, coincides with the
products of one year's observing. So in that one year, 1975, in fact,
we had a flood of objects hitting the Moon, which actually were also
hitting the Earth, and they all were present, apparently, in the same
stream, as was responsible for the Tunguska object in 1908 which, as
you recall, also arrived the end of June. In fact, this end of June is
an interesting time. It's the time when we pass through the Taurid
stream, going in one direction. And the other direction is, in fact,
the beginning of November, and you can see some signs of that in this
same diagram.

This observation was a unique observation of a great swarm of
fireballs, or meteoroids, that nobody had ever observed before and has
never observed, properly, since. And yet it's there. And interestingly
enough, though I just said we've never seen it, there are signs of it
in the meteor observations if you start scouring through them, and with
care. We know that there is a huge swarm of this material in the Taurid
stream, which is moving around in what is called the "mean motion
resonance." That is, Jupiter strongly influences it's orbit, and there
is every reason to believe that because all this material is in this
huge resonance, there is some huge source that has been feeding these
meteoroids into it, down through the millennia.

That you could not have known before 1975. But, in fact, the results
have gradually become clearer and clearer to us in the last twenty
years. This is just to remind you of a picture you have seen already,
I'm sure, of the Tunguska event, the sort of thing it does. It is a
dramatic type of explosion. It doesn't extinguish dinosaurs because
it's localized. But it's easy enough to picture an object which is,
let's say, two or three hundred meters in size rather than the fifty to
one hundred meters which we believe the Tunguska was, and recognize
that it will obliterate a very, very broad area indeed. In fact, its'
effects would be quite dramatic and certainly might wipe out a small
nation, and seriously perturb a civilization.

What you're looking at here is an illustration of the orbit of the
Earth around the Sun, but I'm superimposing on it some orbits of some
objects in the Taurid meteor stream, just to give you a feel for what's
going on. There is the stream. It's an elliptical stream. The period is
typically about three and one third years. It includes the well-known
comet, comet Encke. And Jupiter, which doesn't appear on the diagram is
just off.

The orbit, if you like, embraces the picture. The Taurid stream then
reaches out to almost as far as Jupiter. And so we have a bulk of
material circulating in this very, very broad stream. It takes a couple
of months, at both intersections with the Earth's orbit, for us to
cross. And there it is at the top at the beginning of November, and
coming away from the sun at the bottom at the end of June.

If I might just put the picture of the fireballs back on which you
were looking at yesterday, we'll try and get it all onto the screen,
and I'm going to leave it up because I want it to get embedded into
your gray cells as one of the more revealing diagrams, as to what is
going on in the inner solar system. All you really ought to look at is
the top right hand diagram. The bottom right hand one is just an
improvement of it. It shows the sudden surges in the fireball flux,
which lasts for something like fifty years, which I was describing to
you yesterday. Now these surges have correlated with them an increase
in the flux of Tunguska sized objects. So where the normal flux of
Tunguskas, which is related to the background or subordinate level in
that plot, is something like one every century or so, the rate goes up
to like one a year or so for these periods of time. And there's nothing
wrong with the sense that the world is in some kind of danger, under
those circumstances, in order to over-exaggerate it because any one
country, no doubt, would escape. In fact, many countries would escape.

The danger, nevertheless, is unpredictable and given the fact that
we now live in a global village there's no question we would all be
aware of this kind of event in our locality, as people indeed were in
the past, and they feared it.

The interesting thing is to look at the left hand diagram, which is
a plot of the same fireballs, per month, per century. And the important
point to note is that it's not uniform across the board. When you get
the peaks you see it concentrating in mid summer and early November.
The actual peaks are related to enhancements of the hub of the
meteoroids in the stream that I've been talking about, the Taurid
stream.

And the broad picture is that in spite of your preconceptions in
this business there are Shoemaker-Levy type events occurring which
influence, or affect, the Earth. And the debris, instead of all piling
into the planet in one go, in this instance, runs around the orbit for
several circulations-maybe a dozen or so-and the planet is at risk, as
it were, again, and again, and again. And with that kind of situation
you do get conscious of your environment and some of the possible
dangers that it might carry.

I'm gong to follow my script a little at this point, if you don't
mind, and because I tend to meander when I talk and I want to try and
fit as much as I possibly can into the available time.

I want to summarize the meaning of this diagram, which I'm going to
ask you to gaze at, endlessly. Chinese fireball observations indicate
that there is a great swathe of disintegrating dark debris circulating
in the inner solar system, occasionally producing Tunguska and
super-Tunguska bombardments.

This is a picture that is unlike the one that you believe you know
has been going on for the last two millennia, which are within recorded
historical time rather than, let's say, mythological and
protohistorical time. It's meant to be the bit of history we understand.

This swathe cuts across the Earth's orbit around mid-summer and
Halloween, in a huge elliptical torus, reaching out short of Jupiter,
as I have described. And its further disintegration is responsible for
the system we know of as sporadic meteors, which all lie close to the
ecliptic and the zodiacal dust, as I've described.

It is hardly possible to understand all this material steadily
disintegrating into dust except in terms of a once very massive comet
at the heart of the Taurid electrical torus, with an orbital period of
about three and a third years. Indeed, if this torus were now visible
you would see it like a huge additional Milky Way in the sky, slightly
inclined to the ecliptic and for all the world in a configuration like
one that was described in Plato's Timaeus , in his account of God's
construction of heaven and Earth. I don't know how many of you recall
or are familiar with this, but what he does describe is Earth and
heaven being made in the form of a circular belt which is cut into two
strips, and God then places one strip in slight inclination to the
other. And the theorists then get in a bit of a 'tizz trying to explain
this as an earlier account of the ecliptic and the equator.

In fact, the account makes it very clear that we're talking about
material things in both cases, and in fact is more plausibly-much more
plausibly- related to the Taurid stream in a more visible state, as it
would have been in two or three thousand, and more, years ago. Heaven
would be the home of the gods-being the Taurid torus-while Earth would
be the home of the planets, being the plane of the ecliptic.

People in the past, of course, have suspected these slight shifts of
name for the ecliptic and an individual planet. In fact, we can see
some reason behind other descriptions that are on offer to us, where we
have some part of the cosmos described as a glowing cavern carved out
of the cosmos.

Early pictures seem to describe heaven in this way and it may well,
again, be that they were describing early sightings, if you like, of
this Taurid stream. I do want to get the message to you that in spite
of your being unfamiliar with it, and in spite of it being so difficult
to see, it is a very massive system. It does correspond to the material
of a comet, a hundred kilometers or more in size-far, far larger than
anything that we are normally familiar with but, of course, we do see
these things further out in the solar system.

This kind of picture, my colleague, Bill Napier, and I, were
describing in the book that Irving kindly mentioned, The Cosmic
Serpent, twelve years or so ago, and that was a time when we were
actually predicting that this stream would have asteroids in it. Of
course, that was not known at that time; they had not been observed.
But we now live in a time when many asteroids have now been discovered
in the stream. So the kind of logic that led to this picture has really
been firmed up considerably by the fact that we now see the very things
that we thought must be there.

So, it is now the home of about a hundred Earth-crossing asteroids,
not all of which, of course, we have yet seen, and these are just part
of the dark but disintegrating debris. It's not too much to suppose
these were all once dying cometary gods. Within the stream is one known
comet-comet Encke, which I've mentioned, and this is getting steadily
fainter. And if you wanted to transfer this two or three thousand years
ago, you might like to think of this as a dying cometary god.

I'd like to remind you now that one of these peaks that you are
looking at here-the 1601 occurs round about 1640 through 1680, and it
coincides with the end of the Thirty Years War in Europe, and the Civil
War in England. I mentioned this briefly last night. Cromwell, and
others of that time-I only name him because, of course, he's a familiar
name to you, but there are many others-described all the upheaval of
the time, in millennarian terms, as due to "God's revolution" only a
century after Copernicus' De Revolutionibus.

My point here is that the word "revolution" is popularly used
nowadays in a social sense. It didn't have that at the time Copernicus
was writing; it acquired it. It acquired it at the time of the English
Civil War. And it was because of the perception that things in the sky
were driving things, terrible things, that were happening on the
ground. Only three hundred and fifty years ago, then, mankind was still
in the era of an invisible sky god from a once visible heaven
associated with angels, fallen angels, and dangerous demons hurling
thunderbolts.

We have to get rid of the idea that our ancestors thought that space
was empty. They didn't have [the] specialized astrophysical knowledge
that has allowed me to build the Taurid stream for you; they just knew
it was there. That's really rather a remarkable thing. We've had to
unlearn that knowledge in the last three hundred and fifty years in
order to put ourselves in the state of rediscovering it.

So, what was The Enlightenment only forty years after Cromwell? It
was the pragmatic English decision to get rid of all the angels and
demons, invisible sky gods, and a once visible heaven. It was the
decision to stop worrying about the evidence of fireballs and the
supposed behavior of comets. It was a decision to reconstruct the
cosmos without heaven in the solar system and put it in the ether or
outside the cosmos altogether of infinity al la Bruno. It was
the decision to create a purified, less frightening cosmos in much the
same way as Aristotle did after Plato. On both occasions we shifted
from astrology to physics, and from a sky of foreboding to a sky of
inspiration, from prison and terror to freedom and hope.

Indeed, the cry of the revolutionary periods of 1640 to 1680 and
1760 to 1800, the time of the American War of Independence, was the cry
of freedom from heavenly oppression, demons, and fireballs.

For the last two hundred years of Enlightenment we have been
rewriting history so that the cry of freedom is from earthly
oppressors. No wonder the world has gone wrong and the astrophysicists
today cannot come to terms with the Taurid torus. I'm really trying to
say that this is just not an astrophysical discovery that we are
talking about. Everything has got to, sort of, turn around in order to
come to terms with what is being said. And this, in a way, is rather
like what Irving was describing beforehand. There is a paradigm shift
involved in recognizing that it's not just ancient history we have got
wrong-it's all history.

So, what is my point? My point is that you do not have to dabble
first in mythology and prehistory and geology, as Velikovsky did, in
order to understand the sky. You first take the modern sky accessible
to science, especially during the Space Age, and you look at its'
darker debris with a view to relating its behavior to the more
accessible human history which we can, in principle, really understand.
And by this approach you discover from the dynamics of the material in
space which I'm talking about that a huge comet must have settled in a
Taurid orbit some 20,000 years ago, whose dense meteor stream for
10,000 years almost certainly produced the last Ice Age.

(Missing Text due to change of tape)

The chance of a collision with Kronos, as with any other comet was,
in fact, remote. And mankind settled into a Golden Age. But some time
at perihelion, around 3,000 B.C., it is likely that Kronos ran very
close to Venus and split, like Shoemaker-Levy. And a trail of new,
dazzling comets circulated around the Taurid stream-evidently, for
centuries. Somewhere in this array still was the Kronos remnant; less
bright, perhaps. And a new leader, Zeus or Marduk, perhaps, much
brighter, together with a new serpentine Milky Way, the home of chaos.

By 2,000 B.C., due to an orbital precession, things got worse, for
the trail was now crossing the Earth's orbit and mayhem ensued. The
Sumerian civilization came to an end under a barrage of Tunguskas,
thunderbolts, all over a period of a couple of centuries and we were
now in a sky of foreboding. Then passed another 2,500 years with Zeus
in decline and Kronos already barely visible, while the latter's orbit
precessed until we come to the next intersection with the Earth's orbit
around 500 A.D. when mayhem again ensured. This time the Roman
civilization collapsed and the dark age was in place. And it was Plato
and the Christians, of course, with their knowledge acquired from the
Magi who had predicted this "end of the world."

In the medieval society which then emerged, it was natural that they
should first invoke the world of demons and foreboding. But eventually
it seemed that the danger was passed, and by the twelfth century the
Europeans were changing back to the Aristotelian picture of inspiration
and supposed enlightenment. The Taurid and probably the Kronos remnant,
are still there, of course.

And the next crossing of the Earth's orbit will be around 3,000 A.D.
There's no guarantee of avoiding additional bombardments before then,
and, of course, there may be another Jesus Christ.

I'm going to come to an end and possibly leave no time for
questions, I'm afraid. But I am told that I'm going to be up here again.

What, then, should Velikovskian's make of all these additions to our
cosmic environment? Well, my first point, I think, is that we do not
need to move the planets around to get catastrophes. Super Tunguskas
will do it all.

Point two-everything we say makes no challenge to conventional physics, or astrophysics, for that matter.

And point three-everything we say, as Velikovsky would have wished, does make a challenge to conventional history.

The new picture is one of punctuated peace. It is the picture, I
would suggest, enunciated by both Spengler and Toynbee (not the world's
most favorite historians nowadays), one in which new cultures emerged
from chaos, with a shout, to become civilizations which then stagnate
or decline, slowly. Only with a fresh cosmic crisis do they climb to
new heights or collapse altogether, providing us with a new paradigm
shift.

The picture I am describing is, again, rather like the one that
Irving Wolfe was describing previously. I would like to follow Irving
Wolfe here, and suggest that we are, indeed, approaching the position
now when we can reconstruct catastrophic history and demonstrate it as
evidence for the controlling influence of one giant comet over the last
20,000 years of evolution.

There is nothing very arbitrary about introducing giant comets to do
all this. The fact is, that we see them around. The idea that giant
comets dominate evolution is very much in keeping now with the
discovery, further out in the solar system, of objects like Chiron
which are known to come into the inner solar system. The dynamics do
it. They are bound, some of them, to settle in the way this other
object that I have been talking about, has been.

These objects are also found among the long period comets from the
Oort Cloud, and astronomers are perfectly capable of constructing
perfectly respectable physical pictures of how these giant comets are
transferred from the remote Oort Cloud down into the central solar
system, almost as a matter of regularity. Thus, we argue that the
perturbation of the Oort Cloud determined the long-term arrival rate of
giant comets attacking the Earth. If so, due to the Sun's motion up and
down in the galactic plane, we can predict the periodicity in
terrestrial evolution.

This periodicity is certainly now observed and correlates
exceedingly well with the Sun's present position in the galactic plane,
and with its motion up and down in the galactic disk. All of these
things are kind of rather well known and understood by astrophysicists.
The period also fits the dark matter which we now believe to be in the
galactic plane and which we infer from other kinds of observations
altogether.

In fact, too much is now hanging together in this wide range of
information that I am giving you, to really doubt that it's got the
bare bones essentially there. And we may now be in a very interesting
position of being able to say something about the dark matter itself.
It could, indeed, be cometary material of some kind, and it could be
the very material that makes the stars that we see being made in the
spiral arms in the galactic plane. What I'm trying to say is that
through grasping at some of these complexities associated with our
history-and we have learned more about comets than we would otherwise
have done from pure physics alone, carried out, if you like, in its
very pure laboratory. The historical findings, I would maintain, and
I'm sure Velikovsky would argue in a very similar way from his picture
(not perfectly correct as it was) ...

The historical findings, in other words, are highly relevant to
astrophysics. They're a sort of way of integrating all this knowledge.
It has a completeness which a former picture did not have.

Thank you.

(Question and answer period follows)

Questioner 1: Victor, I see some irony in the
statement that we don't have to move around the ... I don't know, maybe
we don't have to, but I just want to remind you that you have ... of
course.

But two issues of Scientific American ago, mainstream
astrophysicists ... the idea that the Moon was created out of a clash
of the Earth and Mars, so we have here, somehow, intriguingly, a
movement out of mainstream ... scholars to planets being moved around,
and even clashed, to create the Moon. And then we have more or less a
near-catastrophist approach which is rather not cautious to make ...
it's just a statement, not a question.

Clube: Right. No comment then.

Moderator: That's the Oxford debating experience!

Questioner 2: (question not asked from microphone)
... kind of an intellectual construct in bringing echo(sp)-physical
evidence that a field of cometary material was ... out beyond our solar
system, as the source of comets?

Clube: Well, I know the comet. I don't really
believe it at all. We do see the Oort Cloud. What we observe are the
comets from the Oort Cloud. And it's understanding how these comets
could come to us to be seen that leads us to build sensible models of
the Oort Cloud. OK, it's a construct.

But then, perhaps, so too, is a hydrogen atom. It's one of the more
plausible constructs of astrophysics, if I could put it that way. It is
much more solid than many of the things we heard criticized a little
while ago in the cosmos at large. It's a fact!

Van Flandern: On that part not all astronomers
agree that the Oort Cloud is a plausible construct. But my question for
you is- you argued that at the end of 500 AD there probably was some
involvement with the Taurid stream and the decline of the Roman Empire.
Now, inside recorded history we have details of how the Empire came to
an end, but I don't recall any details ... that influence that.

Clube: That is correct and it's certainly worthy of
a lecture in its own right. I have written a little on this, and I
think the thing that one has to address is that it is well known that
this was a period, first of all, when people thought the end of the
world was coming. OK? And I pointed, already, to you the evidence that
there were fireball flux, which is free for interpretation and would
guide you to this view.

Now, one of the problems with the management of the Roman Empire was
the fact of what is called "deserted lands." Great tracts of land were
apparently deserted and people were on the move. It was a period of
migrations, as you know. And it was the management of this that was,
clearly, a severe problem- increasingly a severe problem for the Roman
Empire from round about 200 AD onwards.

And one can formulate, I would submit, an interpretation of all that
was going on in terms of this problem getting more and more acute until
you come to the time of the initial Dark Age in Britain, by which time
chaos was almost intervening. We have very good records, in Britain, at
least, of survival really going back to subsistence level for two
generations. And some very interesting evidence from famous author
Gildas, who described the fire of righteous vengeance which came down
and caused a great catastrophe in England in 441 AD.

Now, what I'm really getting at here is that everybody knows about
this catastrophe. There are endless attempts to explain it. None of
them are normally in terms of the obvious-the one that described the
astronomical event.

What I am trying to say is that there is evidence for Tunguska
events throughout that period. It's simply put aside as not relevant
because the historians are guided by astronomers who would never think
of such a thing.

Gravity
fluctuations beneath East Antarctica measured by GRACE satellite.
Denser regions appear more red; the location of the Wilkes Land crater
is circled (above center).

The crater's location, in the Wilkes Land region of East Antarctica,
south of Australia, suggests it might have instigated the breakup of
the so-called Gondwana supercontinent, which pushed Australia
northward, the researchers said.

"This Wilkes Land impact is much bigger than the impact that
killed the dinosaurs, and probably would have caused catastrophic
damage at the time," said Ralph von Frese, a professor of geological sciences at Ohio State University.

How they found it

The crater is about 300 miles wide. It
was found by looking at differences in density that show up in gravity
measurements taken with NASA's GRACE satellites. Researchers spotted a
mass concentration, which they call a mascon-dense stuff that welled up
from the mantle, likely in an impact.

"If I saw this same mascon signal on the Moon, I'd expect to see a
crater around it," Frese said. (The Moon, with no atmosphere, retains a
record of ancient impacts in the visible craters there.)

Airborne
radar image of land elevation in East Antarctica. Higher elevations
appear red, purple, and white; the location of the Wilkes Land crater
is circled (above center). Image courtesy of Ohio State University . An
inset of the Chicxulub crater is included for comparison.

Smoking gun?

The Permian-Triassic extinction, as it is known, wiped out most life
on land and in the oceans. Researchers have long suspected a space rock
might have been involved. Some scientists have blamed volcanic activity
or other culprits.

The die-off set up conditions that eventually allowed dinosaurs to rule the planet.

The newfound crater is more than twice the size of the Chicxulub
crater in the Yucatan peninsula, which marks the impact that may have
ultimately killed the dinosaurs 65 million years ago. The Chicxulub
space rock is thought to have been 6 miles wide, while the Wilkes Land
meteor could have been up to 30 miles wide, the researchers said.

Confirmation needed

Postdoctoral researcher Laramie Potts assisted in the discovery.

The work was financed by NASA and the National Science Foundation.
The discovery, announced today, was initially presented in a poster
paper at the recent American Geophysical Union Joint Assembly meeting
in Baltimore.

The researchers say further work is needed to confirm the finding.
One way to do that would be to go there and collect rock from the
crater to see if its structure matches what would be expected from such
a colossal impact.

On this day in 1664, as described in the book "Cape Cod Historical
Almanac" by Donald G. Trayser, "the people of Cape Cod and other parts
of New England saw the last of a great comet which excited fear and
awe. It appeared November 8th last, and continued to this date, the
third comet witnessed by early settlers in the space of 12 years.

"The first appeared in December, 1652, the second in February and
March, 1661, and the third as noted above," Trayser wrote. "Comets were
fearsome things to people in these days."

Trayser quotes Nathaniel Morton, secretary of Plimoth Colony, who
wrote of the comet of 1663-64 that " ... it was no fiery meteor caused
by exhalation, but it appeared to be sent immediately by God to awake
the secure world."

"Night after night, 'the great blazing starre' was observed in the
southern sky," Trayer wrote, "and for several years after it, all the
calamities and evil things which occurred in the world were ascribed to
it."

At the end of the year [1664] we saw shortly after each other two
tail-stars or comets arising in the sky. The first one, in the
southeast, was to be seen for almost two months. After that another one
appeared in the southeast. The appearance of these celestial bodies,
caused a big panic in the country. The war-fleet was standing by, the
guards of the ports were reinforced, all fortresses were provided with
extra provisions and extra munitions, while cavalry and infantry were
exercising daily. Also was it not allowed to light any lamps,
especially not in the cities along the coast. This fear was caused by
the fact that when the Tartarians invaded the country, there were also
similar signs in the firmament, as well as at the beginning of the war
with the Japanese.

Many a Korean asked us what we thought of it and if we considered
the appearing of these celestials also as a bad omen. We answered that
we, in Holland, usually expected that the appearance of a similar sign
was an omen of one or the other disaster, be it a war, flooding or an
epidemic.

Hendrick Hamel was the Dutch "Marco Polo", exploring Korea in the middle of the seventeeth century.

Space
shuttle Atlantis mission specialist Stanley Love on Feb. 4, 2008 at
Kennedy Space Center in Cape Canaveral, Fla. Love is preparing to make
a spacewalk to attach the European Space Agency's Columbus laboratory
to the International Space Station.

Astronaut Stanley Love will be walking in space today to help attach
yet another new section of the International Space Station, but he has
even bigger plans in mind. He'd like to save the world.

Love, who is aboard the space shuttle Atlantis, has hatched a a plan
with his colleague Ed Lu to prevent Earth from getting hit by an
asteroid.

"Many methods that people have talked about involve things like
nuclear weapons - let's blow it up! Or smash something into [an
asteroid] at eight kilometers per second and blow it apart," Love said.
"Those methods are a great way of getting kinetic energy into the
target, but you are not quite sure what you are going to get after that. Instead of one big rock, you might have a swarm of smaller rocks."

Love's and Lu's plan would send a spacecraft into orbit around any asteroid with Earth in its sights.

"You sidle up next to it, and you just hover there for like a year.
Now you need a good long warning time on the asteroid because during
your year of hovering, because of the very tiny gravitational pull
between the spacecraft and the asteroid, that amount of pull is about
the same amount of thrust as gluing a housefly beating its wings, to an
asteroid," Love said. "A tiny amount of thrust, but build up over a
year, then given 20 years to drift, in that direction, you can turn an
asteroid strike into a miss."

Before he saves Earth from an asteroid strike, Love has to help out
with a spacewalk. The astronomer-turned-astronaut was scheduled for one
spacewalk during STS 122, the current shuttle mission, but because of
the unexpected and unexplained illness of his colleague, Hans Schlegel, he will go out into space twice.

Love and astronaut Rex Walheim will prepare the $2 billion European
Columbus module for installation on the International Space Station.

It's no big deal, he told ABC News, in an interview before his launch.

"Mainly it is an attitude of mental flexibility. Don't be married to
the plan," he said. "You know that at any moment the plan may change
and the finely crafted choreography you worked out may not work out
that day and you may have to do something else."

Love is enthusiastic about his mission.

"I am very psyched in a wow gee whiz way. It is hard to explain. I
think enthusiasm and professionalism go hand-in-hand," he said. "You
are not going to be a very good professional if you don't enjoy what
you doing. But pure enthusiasm without professionalism is dangerous."

He certainly plans to stop once in awhile when he is on the spacewalk and look around.

"There will be times when I need to hang tight, when I don't have
something specific that I have to do and those are the moments that
everyone has advised me, take those moments and look around, savor the
moment - be where you are and appreciate it," he said.

What makes this space shuttle mission to the International Space
Station important? Love says it means the space station will truly be
international now.

"This European community has invested their resources, their people,
and their enthusiasm in building this Columbus module that we are
adding to the space station," Love said. "Right now we have physical
parts of the space station from the United States, from Canada and from
Russia and now we are adding in another partner and that partner itself
is composed of the many member nations of ESA."

The newest partner is the 11-nation consortium of the European Space Agency.

What would he like to do next? Love wouldn't mind going to the moon.
While it may be a forbidding place, so is, he says, Antarctica.

"I imagine the first people to go to Antarctica found nothing there
but ice and wind and cold, now of course Antarctica is like the premier
science lab for the Earth and glaciology and geology and atmosphere
sciences. All this great stuff [is] going on there in this place where
it was worth your life just to look at 100 years ago," he said. "So I
think maybe the moon will be like that in 100 years - an amazing
science lab where people go to find out stuff about our world and our
universe".

As an astronomer he is really hoping for a chance to see the stars from a different angle.

"I expect the light pollution on the space station is as bad as it
is in Houston. I am not sure how good a view I am going to get," he
said. "I have had people come back and say if you get a chance, in the
shuttle cockpit, turn off all the lights during a night pass when
nobody is working and look out the window. It is really cool."

The dinosaurs dominated the landscape for 160 million years, living
over a thousand times longer than modern humans (Homo sapiens first
evolved about 150 thousand years ago). During this vast stretch of time
some dinosaur species became extinct, but overall the impression is one
of an immensely tough class of animals that could endure whatever
hardships the planet managed to throw at it. When the end finally came,
it came from beyond Earth.

A meteorite impact 65 million years ago is the simple explanation
for the extinction of the dinosaurs. The exact details are much more
complex, and researchers are still trying to nail down exactly what
happened. The Cretaceous-Tertiary (K-T) extinction event is like an
ancient tapestry that has become matted and soiled due to time and
neglect. There are hundreds of threads of evidence that need to be
untangled, smoothed out, and put in their proper place before a clear
picture can emerge.

The first, most important thread of evidence is a strip of clay that
runs through rocks around the world. Known as the K-T boundary layer,
this is the line no dinosaur could cross (although their relatives, the
birds, did survive).

In 1980, a team of researchers led by Luis Alvarez and his son,
Walter, discovered that the boundary layer contains a relatively high
concentration of iridium. Iridium is rare on the Earth's surface but is
often found in meteorites. During the molten phase of our planet's
formation, most of the iridium of Earth traveled down with iron to form
the planetary core. The Earth does receive a light surface dusting of
iridium from the occasional meteorites, and some volcanoes can release
iridium if their lava comes from a deep enough source. These events
give the planet's surface a background iridium level of 0.02 parts per
billion (ppb) or less.

Depending on the location of the rocks, the K-T boundary layer has
varying amounts of iridium, but all are far above that background
level. The section analyzed by Alvarez had 9 ppb. Other sections have
upwards of a million times the background level. Luis and Walter
Alvarez surmised that a large meteorite rich in iridium must have hit
the Earth, and the after-effects of the impact led to the demise of the
dinosaurs.

Later, a large impact crater underneath Mexico's Yucatan peninsula
was fingered as the smoking gun. When a meteorite punches the Earth's
crust, some rocks and minerals are vaporized, some are flash heated and
become molten, while others shatter, or become "shocked" in a
distinctive pattern. Samples of the Chicxulub crater had all these
features of a meteorite impact. The crater was dated to be about 65
million years old, the same age as the K-T extinction.

The meteorite that made the Chicxulub crater was 10 to 15 kilometers
in diameter, or about the size of the island of Manhattan. It screamed
to Earth faster than a bullet, smashing open a vast cavern 40
kilometers deep and 100 kilometers across. This crater quickly
collapsed under the force of gravity, leaving a hole 180 kilometers
wide and only 2 kilometers deep.

The energy released by this impact was equal to 100 million megatons
of TNT. In comparison, the 1980 eruption of Mount Saint Helens released
energy equivalent to just 10 megatons of TNT. The atomic bomb that
exploded over Hiroshima released energy equivalent to about 10 kilotons
of TNT (or 0.01 megatons).

The impact obviously destroyed life in the immediate area, and the
shock wave likely generated huge tsunamis and earthquakes further away
from ground zero. Other, longer-lasting effects, such as dust and
chemicals from the vaporized rocks, dispersed around the world.

The debate about the K-T extinction was contentious before Alvarez's
hypothesis, and the discovery of Chicxulub seems to have done little to
stem the often emotional arguments about the extinction event.

At first, some doubted that Chicxulub even was an impact
crater. The structure is buried 1 to 2 kilometers under ground - half
under land and half under the sea floor - and was only discovered by
gravitational and magnetic anomalies from readings taken at the Earth's
surface. However, samples from drill cores helped confirm that
Chicxulub was formed by a meteorite impact.

While most scientists now agree that Chicxulub is an impact crater,
not everyone believes it caused the K-T extinction. For instance, some
wonder if the Chicxulub impact occurred at the right time. Gerta Keller
of Princeton University argues that its true age pre-dates the
dinosaur's demise by 300,000 years. However, other scientists contend
that Keller's sampling method was flawed, and resulted in an inaccurate
date.

Among scientists who agree that Chicxulub was the cause of the
extinction, there are disagreements about the tangible effects of the
impact. Some scientists think so much dust was sent flying high into
the air that the skies darkened for years, halting photosynthesis and
killing plants worldwide. Others contend that the dust wouldn't have
been so long lasting, since rain would have soon cleared the air. Some
have suggested that red-hot impact debris raining back down would have
ignited forest fires worldwide, darkening the skies with black soot.
Another theory suggests that so much sulfur was sent up into the
stratosphere that the rains became like battery acid, poisoning land
and sea.

Finally, there are some who believe that while Chicxulub played a role in the extinction, it was not the primary cause.They are seeking answers beyond Chicxulub, wondering if anything else
could have contributed to the loss of species. The dinosaurs weren't
the only creatures to suffer death and destruction, after all. The K-T
mass extinction event killed at least 50 percent of all the world's
species. Could a single meteorite impact - even one as large as Chicxulub - have dealt such a fatal blow to life?

Just a few years ago, many scientists, especially physicists and
astronomers, considered the Book of Science to be closed in the matter
of what happened at the Cretaceous-Tertiary (K-T) boundary, 65 million
years ago, and why the dinosaurs met their end. It was declared, rather
imperiously, that a large asteroid had impacted the earth, causing much
physical and biological devastation. Many scientific papers are still
being written on this singular period in the earth's history, and the
situation is no longer so clear-cut. We select for brief review four
papers, each with a different perspective.

Occurrence of stishovite. Stishovite, a dense phase of silica, is
widely accepted as an indicator of terrestrial impact events. It is not
found at volcanic sites. Now, J.F. McHone et al report its existence at
the K-T boundary, at Raton, New Mexico. (McHone, John F., et al;
"Stishovite at the CretaceousTertiary Boundary, Raton, New Mexico,"
Science, 243:1182, 1989.) A plus for the pro-impact side.

Evidence of a global fire. Soot
appears at the K-T boundary at many sites, but where did it come from?
Chemical analyses of these soots show an enhanced concentration of
polycyclic aromatic hydrocarbons over soots above and below the
boundary. This is strong evidence of pyrolytic action at the K-T
boundary; i.e., widespread fires. (Venkatesan, M.I., and Dahl, J.;
"Organic Geochemical Evidence for Global Fires at the
Cretaceous/Tertiary Boun dary," Nature, March 2, 1989.) Fire could have
been initiated by either volcanism or impacts.

The evidence of the traps. Traps, like
India's famous Deccan Traps, are extensive flood basalts. In this
paper, basalt flooding has been correlated with mass extinctions of
marine life during the past 250 million years. The Deccan Traps were
formed right at the K-T boundary. Traps could, however, be initiated by
asteroid impact, which could stimulate eruptions. (Rampino, Michael;
"Dinosaurs, Comets and Volcanoes," New Scientist, p. 54, February 18,
1989.)

The dinosaur angle. If dinosaurs were
truly susceptible to extinction by either asteroid impact, widespread
volcanism, or some combination of both, one would expect to find their
numbers and diversity drastically curtailed during Mesozoic impact
events. Instead, the dinosaurs not only survived these impacts but
prospered. Their demise, which began before the K-T event, was probably
not due to either impact or vol canism. (Paul, Gregory S.; "Giant
Meteor Impacts and Great Eruptions: Dinosaur Killers?" BioScience,
39:162, 1989.)

It is unlikely the dinosaurs perished in a
global firestorm triggered by the asteroid strike on Earth 65 million
years ago, scientists have claimed.

A popular theory suggests the impact, which was centred on Chicxulub
in Mexico, generated enough energy to set off a raging worldwide
inferno.

But a new study shows rocks laid down at the time contain little charcoal - a possible tell-tale record of fires.

The researchers have published details of their work in the journal Geology.

The wildfires theory had grown up from previous research. One study
had even found evidence of soot in rocks from around the Earth dating
to the time of the impact.

Sun block

It is thought that in addition to the devastation these fires
caused, the soot thrown up into the atmosphere as a result of the
cataclysmic event may have helped block sunlight, causing global
cooling and a shut-down of photosynthesis.

Plants not consumed in the inferno would have just shrivelled away - so the theory goes.

CHICXULUB IMPACT CRATER

# Approximately 180 km across

# Now buried under one km of carbonate sediments

# Asteroid responsible for Chicxulub was 10 km wide

But now Claire Belcher, of Royal Holloway, University of London in
Egham, has come forward with research that challenges this particular
view of dinosaur Armageddon.

She studied six sites in a transect through the western interior of
North America. Each site dates to the end of the Cretaceous Period when
the impact occurred.

Each of these sites records a geological boundary dividing the end of the Cretaceous period from the beginning of the Tertiary.

This Cretaceous-Tertiary boundary, or K-T boundary, marks the
extinction of the dinosaurs and is thought to be associated with the
impact of a large space object because the sedimentary rocks of this
layer contain large quantities of the element iridium, which is most
commonly found in meteorites.

Charcoal trace

She and her colleagues looked for traces of charcoal in these rocks,
which could only have been produced by burning biomass, such as
vegetation. But they found very little charcoal in these layers.

"It's significant because most people model the K-T boundary in
terms of the thermal energy released," Belcher told BBC News Online. "It's often said that temperatures on the ground reached 1,000 [Celsius].

"But 40% of species survived the impact. How could a small mammal survive temperatures of 1,000 [Celsius]?"

The researchers conclude that North America, close to the site of
the impact, could not have been engulfed by wildfires, as some have
suggested.

Belcher and her co-authors acknowledge that rocks from the K-T
boundary contain soot, but argue there could be other reasons for it
than wildfires.

For instance, the impact could have vaporised hydrocarbons in the
rocks at Chicxulub, creating soot. The fireball that rose over the
impact site could have expanded through the Earth's atmosphere,
spreading soot across the globe.

Soot sweep

Professor Wendy Wolbach of DePaul University, Chicago, US, who
linked the soot with wildfires in research published 13 years ago, said
she had concerns about the conclusions of the Belcher study.

"I'm not convinced that they can tell the difference between coal and charcoal. The rocks they studied are loaded with coal.

"If there's any difficulty in making that recognition, their conclusions are not sound," said Professor Wolbach.

She added that it was possible Belcher and her colleagues had
expertise she did not. But Professor Wolbach pointed out that the
team's procedures for identifying charcoal were not made explicit
enough in their published scientific paper.

"The new study is very exciting. If correct, it may help narrow the
field. But I wouldn't be so quick to exclude the wildfire theory; it
still needs to be looked at," said Kevin Pope, chief scientist at Geo
Eco Arc Research in Aquasco, US.

"The problem with the wildfire theory is that it is based on computer modelling and theoretical arguments."

Pope said he favoured the theory that the asteroid strike released
sulphate aerosols from impacted rocks. In the atmosphere, they would
have reacted with water to form sulphuric acid clouds.

These clouds could then have expanded over most of the Earth to
block out the Sun, causing global cooling and a shut down of
photosynthesis.

Comment: What
they didn't consider is multiple smaller impacts as well as a larger
one off Yucatan, AND overhead cometary fragment explosions.

June is a time for beach parties and barbecues. It is a time for
wildflowers and warm breezes and slow summer evenings. It is a time
when our sun-orbiting planet cuts across a trail of cosmic debris,
scattered by a monster comet, that one fine day may visit a holocaust
upon us.

So says astrophysicist Victor Clube of Oxford University. He's been
studying the Taurids--a meteor shower that strikes Earth each year in
late June and again in November. The Taurids are not nearly as
spectacular as, say, the Perseids of August; in June they're not even
visible, because they approach from the dayside of the planet. But
Clube and his co-workers think the Taurids are underrated. The meteor
stream, they say, includes rocks so large--as much as a mile
across--that to see one up close would be to lose a city, a continent,
or more.

The evidence comes in part from history. In the early morning of
June 30, 1908, a huge fireball exploded in the sky above Siberia with
the force of a 20-megaton nuclear bomb, leveling 400 square miles of
remote forest around the Tunguska River. The glow lit up the sky as far
away as Western Europe. The Tunguska object, Clube says, was a 150-foot
comet fragment--one of the Taurids.

Another near miss may have happened in 1178. One night in late June,
according to a monk named Gervase of Canterbury, eyewitnesses saw a
flaming torch on the upper horn of the new moon, which thereupon
throbbed like a wounded snake. The throbbing could have been a dust
cloud kicked up by a meteorite; a 13-mile-wide and apparently fresh
crater named Giordano Bruno seems to be in the same spot as the flaming
torch. If so, then the Earth narrowly missed being hit by a meteorite
about a mile across--large enough to have devastated a continent.

The moon appears to have been pounded again by the Taurids as
recently as 1975, when seismometers left behind by Apollo astronauts
picked up the impact of a huge swarm of boulders. The onslaught started
on June 22.

Clube and his colleagues believe a single cosmic marauder lies
behind all these events. Meteor showers are debris shed by passing
comets, and usually the pieces are no more than a few inches across. If
Clube is right, however, the Taurid meteor stream includes some large
chunks: in addition to the historical impactors, Clube says, there are
half a dozen full-size asteroids whose orbits place them squarely in
the stream.

Clube and his colleagues argue that the Taurids' range of orbits
indicates they were all shed by a huge comet, originally 100 miles
across or more, that entered the inner solar system some 20,000 years
ago. The comet's orbit took it inside that of Mercury, close to the
sun. By 10,000 years ago it was desiccated and brittle, and since then
big chunks have been breaking off each time it passes the sun. One of
those chunks, Clube thinks, is a comet called Encke. But the core
object itself may still be out there. We suspect that the source of the
Taurids is in an orbit similar to Encke's, going round the sun every
3.39 years, says Clube. We think we're on the verge of finding it.

Clube believes his killer comet sends bursts of Tunguska-size
objects our way every few thousand years or so, and that in the past
the dust clouds raised by such impacts have plunged Earth into cosmic
winters and perhaps even full-blown ice ages. But he has yet to
convince most astronomers that his historical evidence amounts to more
than coincidence. It's quite possible some of the June events fit in
with a single object, but I think Victor may have turned it into a bit
of a conspiracy theory, says Brian Marsden of the Harvard-Smithsonian
Center for Astrophysics.

What many astronomers do agree on, though, is that the risk of a
large impact, while perhaps not as great as Clube suggests, is worth
taking seriously. A committee of NASA experts has recommended that a
global network of telescopes be set up to hunt for potential impactors;
a second committee is expected to urge NASA to develop a way of nudging
an incoming rock out of our way, perhaps with a neutron bomb. After a
decade of growing awareness that Earth has been blasted in the past, a
consensus seems to be emerging: if we don't want to go the way of the
dinosaurs, the danger of an impact--in June or any other month--is one
we should not ignore.

Last time I said I was going to talk about how much your "glorious
leaders" really hate and despise you and how they are plotting your
deaths while most of you are so screwed up that you not only do not see
this, you actually dance blithely toward disaster for yourselves and
your children. Well, I'm going to get there, but first, I want to tie
up a few loose ends and reiterate a couple of points.

As I mentioned in my previous article on this topic, the Discovery Channel special Super Comet - After the Impact,
places the comet that wiped out the dinosaurs in a modern setting,
using the same type of cometary body assumed to have caused the
extinction of the dinosaurs, the same size, same impact location, and
utilized all the computer modeling they have done on this past event to
try to show what might happen (and to show what they think happened
then).

Studies of the history of the Earth via various scientific methods
show us that there are relatively long periods of "evolution"
punctuated by rapid, overwhelming changes we call catastrophes. Many
scientists have noted the periodicity of these punctuational events.
What no one seems to know for sure is the mechanism that induces these
definitely periodic catastrophes.

It is suggested that the periodicity of these events relates to
galactic cycles and there is good evidence for this view presented by
Victor Clube in his book The Cosmic Winter. (You can really forget the nonsense going around about "Planet Nibiru" and "Project Camelot").
He suggests that galactic tides induct giant comets into our Solar
system and it is their disintegration products which interact strongly
and directly with the Earth with variable results at different (and
very frequent!) periods which results in the variations in the
geological record. Clube demonstrates that the breaking up of a giant
comet produces a wide range of debris from objects 10 km across, to
hundreds or thousands of 1 km sized bodies, to multiple swarms of
sub-kilometer sized bodies. Many of these bodies have sooty, black
surfaces making them almost impossible to see and many of them are in
an orbit very similar to the Taurid meteor streams, though a few may be
in an orbit rotated about 90 degrees. Clube posits that many (if not
most or all) of the asteroids in the Solar system split from a giant
comet (or many of them) thousands or tens of thousands of years ago,
and it is the streams of debris that pose the most serious and
immediate threats to our planet.

For example, one of the large asteroids in an Earth-crossing orbit
is named Hephaistos. It is about 10 km in diameter, about the same size
as the asteroid that is depicted as striking the earth in the
above-mentioned movie (the dinosaur extinction model). It is true that
the effects of the impact of such a body would be felt globally, but it
is not so clear that it would be exactly as "global" as depicted in the
movie.

Nevertheless, the connection between a single impactor and past mass
extinctions has been made and popularized widely, and this may be
unfortunate considering the issues of more frequent and less "global"
events that Clube addresses.

The problem is, as Clube points out, a solitary large impact is,
from an astronomical point of view, quite unlikely to be the only
agency at work in such extinctions. Further, when one considers the
details of the evidence, both astronomical and geological, many
discrepancies in the single impactor scenario begin to emerge.

When the Alvarezes, pere et fils, came across the iridium
layer at the K-T extinction boundary, announcing that iridium in those
amounts could only be thrown up by the impact of a large meteorite,
this shocking idea was taken up gleefully by the press and everyone was
on the hunt for iridium.

Clube points out that there are several problems with the "single
impact" interpretation of the presence of iridium at the extinction
boundary. The first problem is that the concentration of the element is too high.
Why? Well, because if it were a single, giant impactor, such an
asteroid would excavate several hundred times its own volume of Earth
crust material and blow it into the atmosphere mixed with its own
material. This means that the iridium would be significantly diluted
and would not precipitate on the planet in such concentrations as have
been found. However, at many of the sites examined, it is noted that
the iridium has been diluted by only 20 times its own volume (keeping
in mind that the iridium in the comet/asteroid is already only a
percentage of the total volume of the extraterrestrial body!)

Additionally, other chemicals associated with the alleged single
impact event do not fit the stony meteorite theory very well. There is
an abundance of rare elements such as osmium and rhemium; enormous and
overabundant common elements such as antimony and arsenic. In respect
of this finding, Clube points out that, after a January 1983 eruption
of Kilauea, particles collected from the volcano were found to have
high concentrations of arsenic, selenium and other elements found in
high abundance at the extinction boundary. These volcanic particles
were also found to be very rich in iridium. Clube suggests that the
iridium anomaly may, therefore, be a big red herring. He notes: "...it
is interesting to speculate whether, had a volcanic source of iridium
been known in 1980, a meteorite impact would have been suggested" by
the Alvarezes?

Probably not.

So, that was probably a good thing because it at least drew press
attention to the matter since Clube also points out that there is an
impressive amount of evidence that the extinction event was not just a
process of evolutionary change and decay. Catastrophic changes - a
profound ecological shock - took place across the Cretaceous-Tertiary
boundary, and the devastation was certainly sudden. So the Alvarez
theory opened the door to consider that in a world that was tightly
bound up in Uniformitarianism.

Among the interesting finds at this level of Earth's history is that
very large amounts of soot are also present at the extinction boundary.
The conclusion is, of course, that global wildfires were raging during
the extinction event. The movie tried to depict that with computer
models (made on the assumption of a single large asteroid impact) which
had the entire atmosphere of the earth heating up to the point where
things just ignited spontaneously. That may not be exactly how things
happen even with a very large meteor impact.

The
thin clay layer that marks the boundary between the Cretaceous and
Tertiary rocks. This layer has been found at many localities around the
Earth. It is a a thin layer of material all around the earth which
contains a large amount of the rare element iridium, plus soot from
widespread fires.

Another point that Clube makes is that there is not a trace of
meteoritic debris in the form of stony inclusions in the sediments.

I won't go into all the details; suffice it to say that it begins to
look like the stray impact of a single 10 km wide asteroid is not the
cause of the global extinction after all.

What is a realistic scenario?

Clube presents the evidence that this extinction event was an
episode of bombardment of many, dozens, hundreds, thousands of cometary
fragment and/or meteorite type bodies, some of them large, liberating
copious amounts of meteorite dust in the Terran atmosphere, many of
them exploding overhead in rains of fire. These swarms would be
"swimming" in streams of comet dust - tons of it - which would also be
loading the atmosphere and precipitating onto the earth over months and
years. The high concentrations of iridium found at the dinosaur
extinction boundary at several localities, and the absence of bulk
meteoritic debris, are hard to explain in terms of a single big bang
but easily understood in terms of zodiacal dust as a provider of the
input. Added to this, there is increasing evidence for a multiplicity
of impacts at the dinosaur extinction boundary, as well as at other
points of global catastrophe such as the Permian - Triassic (P - Tr) extinction event.
The swarm theory also easily accounts for the huge amounts of soot at
the boundary. An Earth ablaze is within the capacity of an
exceptionally intense swarm to produce, but probably beyond that of
even a 10km wide single impactor. In short, the extinction of the
dinosaurs may very well have been a complex, traumatic, and prolonged
affair.

Clube proposes that the Earth itself is a storehouse of information
about its interactions with the Galaxy, and that it is the Galaxy
itself, and Earth's position in it, that drives the cycles of
extinctions mainly because the cycles of events best fit known galactic
cycles.

The one thing that stands out from all of the evidence is the
importance of very large comets that enter the Solar System and break
apart, leaving streams of debris that interact with our planet for
millennia after the parent body or bodies have been captured and torn
apart by intra-solar system forces. That such bombardments of the earth
have occurred at other times is becoming more widely known, witness the
work of Richard Firestone, Alan West and Simon Warwick-Smith who have
identified the Carolina Bays as "air impact" craters from overhead
cometary explosions exactly like that of Tunguska. In fact, similar
"craters" were found in the Tunguska region with the exact same
morphology. This even has been dated to about 12,500 years ago and was
global in extent and cataclysmic in effect. Life on Earth almost came
to an end. What is frightening about this even is the sheer numbers of
craters - upwards of 50,000 of them.

The largest crater in this particular image is approximately 1.4 miles across

Companion Star?

Clube mentions the companion star hypothesis briefly, noting that
"Certainly the companion-star hypothesis adopts the central mechanism
of the galactic one, namely the creation of comet showers through
regular comet cloud disturbances." He then dismisses this as facing
"insuperable problems." The "insuperable problems" are the proposed
orbital periods for the hypothesized companion star and his idea that
there would be far more cratering if the motive mechanism was a
companion star. He may be entirely correct and his theory of galactic
tides and comet birth in the cold, dark reaches of space certainly
deals with the main elements of what we know about our celestial
environment. As he notes:

The astronomical framework, grounded in celestial observations, is
the basis for the theory of terrestrial catastrophism described here.
... It is in our view essential , if one is to arrive at a true
picture, to take account of all the relevant evidence: "hard evidence"
in the geologist's sense has to be coupled with some respect for hard
astronomical facts as well. Put another way, we do not need a 1 - km
asteroid to land in our presence to demonstrate the amount of kinetic
energy it will release. In particular, the correct picture must explain
recent as well as past events in the terrestrial record. Thus the giant
comet, and indeed the historical record, are essential elements in the
quest for overall truth. It is this inextricable linkage between the
very recent and the very remote past which lends urgency to the study:
if we get the grand picture wrong, the next set of old bones in the
ground could be ours.

We have presented some good evidence in this series of articles that
Clube's ideas are very likely correct or darn close: the earth has been
repeatedly and regularly showered with extraterrestrial debris of some
sort, and these showers have been generally disastrous from local
scales, to regional, national, and even continental. It seems clear
from the evidence that history itself is not a process of evolution,
but more often, devolutionary as each cosmic crisis has either resulted
in "survival of the lucky," as opposed to the fittest, and the more
recent ones have been amplified or utilized by ruling elites to pursue
their own agendas. On other occasions, the Earth has suffered insults
that have hardly turned a head in the human population. Tunguska was
one such event.

Tunguska

Just after 7:15 a.m. local time on 30 June 1908, in the central
Siberian plateau, there took place an impact of ferocious intensity.
Yet so isolated and vast is this region (half as large again as the
USA), it was almost twenty years before the Western world became aware
of the event.

On the night of 30 June and 1 July, the sky throughout Europe was
strangely bright. Throughout the United Kingdom, over 3000 miles from
the point of impact, it was possible to play cricket and read
newspapers by the glow from the night sky. From Belgium came
descriptions of a huge red glow over the horizon, after sunset, as if a
great fire was raging. This strangely bright sky was seen throughout
Europe, European Russia, Western Siberia and as far south as the
Caucasus mountains. Photographs were taken at midnight or later, with
exposures of about a minute, in Sweden, in Scotland, and as far east as
the university city of Kazan, on the banks of the river Volga....

Much comment was excited in newspapers and learned journals at the
time. Some thought that icy particles had somehow formed high in the
atmosphere and were reflecting sunlight. Others considered that a
strange auroral disturbance was involved. The Danish astronomer Kohl
drew attention to the fact that several very large meteors had recently been observedover Denmark and thought that comet dust in the high atmosphere might
account for the phenomenon. But there was no agreement as to what had
happened.

Over 500 miles to the south of the fall, a seismograph in the city
of Irkutsk near Lake Baikal, close to the Mongolian border, registered
strong earth tremors.

Nearly 400 miles south-west of the explosion, at 7:17 a.m. on 30
June, a train driver on the Trans-Siberian express had to halt the
train for fear of derailment due to the tremors and commotion.

Fierce gusts of wind were felt in towns 300 to 400 miles away.

In an Irkutsk newspaper dated 2 July it was reported that, in a
village more than 200 miles from the Tunguska river, peasants had seen
a fireball brighter than the sun approach the ground, followed by a
huge cloud of black smoke, a forked tongue of flame and a loud crash as
if from gunfire.

"All the villagers ran into the street in panic. The old women wept and everyone thought the end of the world was approaching."

[...]

Local Siberian newspapers carried stories of a fireball in the sky,
and a fearful explosion, but by the autumn of 1908 these stories had
died out, and they went unnoticed in St. Petersburg, Moscow and the
west. The region was arguably one of the most inaccessible places on
Earth, in the centre of Siberia. ... However, rumours of an
extraordinary event persisted, transmitted back by geologists and other
intrepid researchers working in the area. These attracted the attention
of a meteorite researcher, Leonard Kulik,... It was not until 1927 that
an expedition ... led by Kulik, finally penetrated to the site of the
1908 explosion.

[...]

The energy of the explosion has been calculated from the extent of
the flattened forest and from the small pressure waves which arrived at
the speed of sound and were recorded on barographs around the world.
... The wave trains were unlike any others which had been recorded up
until that time but resemble those obtained from a hydrogen bomb
explosion. It seems that the impact had an energy of 30 to 40 megatons,
about that from a few dozen ordinary hydrogen bombs....

The date of fall (30 June) corresponds to the passage of the Earth through the maximum of the Beta Taurid stream. From this and its trajectory, it appears that the Tunguska object was part of the Taurid complex. Probably the Earth passed through a swarm within the stream.

This diagram shows the area of damage in Tunguska as compared to the size of Washington D.C.

The occurrence, this century, of an impact with the energy of a
hydrogen bomb does give cause for some concern, and it is interesting
to speculate on whether one's historical perceptions would be quite the
same had the bolide struck an urban area or a city. As it happens,
however, the Tunguska impact is fairly trivial:

In this year, on the Sunday before the Feast of St. John the
Baptist, after sunset when the moon had first become visible a
marvelous phenomenon was witnessed by some five or more men who were
sitting there facing the moon. Now there was a bright new moon, and as
usual in that phase its horns were tileted toward the east; and
suddenly the upper horn split in two. From the midpoint of the divisin
a flaming torch sprang up, spewing out, over a considerable distance,
fire, hot coals, and sparks. Meanwhile the body of the moon which was
below writhed, as it were, in anxiety, and, to put it in the words of
those who reported it to me and saw it with their own eyes, the moon
throbbed like a wounded snake. Afterwards it resumed its proper state.
This phenomenon was repeated a dozen times or more, the flame assuming
various twisting shapes at random and then returning to normal. Then
after these transformations the moon from horn to horn, that is along
its whole lengthe, took on a blackish appearance. The present writer
was given this report by men who saw it with their own eyes, and are
prepared to stake ther honour on an oath that they have made no
addition or falsification in the above narrative.

This curious report is written in the chronicles of the medieval monk known as Gervase of Canterbury. The year of the event was AD 1178 and the date, 18 June on the Julian calendar, converts to the evening of 25 Juneon the modern Gregorian one. If real, it is clear that some
extraordinary event on the Moon is being described and the meteorite
expert Hartung proposed that what was observed and recorded 800 years
ago was the impact of a body on the Moon. The flame, he suggested, was
the writhing of incandescent gases, or sunlight reflection from dust
thrown out of the crater. The blackish appearance of the Moon along its
whole length was a temporary suspension of dust buoyed up by a
transient atmosphere. [...]

Hartung deduced that if there was a crater, it would be at least 7
miles in diameter, possess bright rays extending from it for at least
seventy miles, and would lie between 30 and 60 degrees north, 75 and
105 degrees east on the Moon. ...

As it happens, there is one crater with the predicted characteristics exists, a crater named after the seventeenth-century heretic Giordano Bruno.
This crater is located at 36 degrees N and 105 degrees E, within the
predicted area. It is 13 miles in diameter and is distinguished by its
remarkable brightness, and by the brilliant system of rays which extend
several hundred miles out from it. [...]

It should be noted that NASA has attempted to debunk Hartung's theory, saying:

Such an impact would have triggered a blizzard-like, week-long
meteor storm on Earth -- yet there are no accounts of such a storm in
any known historical record, including the European, Chinese, Arabic,
Japanese and Korean astronomical archives.

Well, we know from our current survey that this is not necessarily
so. There could have been impacts on the earth that no one knew about -
witness Tunguska - and it doesn't necessarily follow that an impactor
on the moon would trigger a blizzard of meteors on Earth.

Back to Clube:

It is the fate of all species to become extinct and
most manlike species have already done so. Over and above extinction,
large population fluctuations take place in nature, sometimes within a
few years. The controlling factor is often climate, and Earth's
climate, in turn, can be greatly affected by its astronomical
surroundings.

It has been suggested that the current "climate change" issues are
due to the earth moving through cosmic dust clouds. It could even be
that such things as "chemtrails" are a result of such dust loading in
the upper atmosphere.

The two and a half centuries which lay between the
Gervase chronicle of 1178 and the onset of the Black Death in Europe in
1348 saw 'an acute crisis developing in human affairs'. One chronicler
at least reports of the most immediate cause of the plague in 1345 that
"between Cathay and Persia there rained a vast rain of fire; falling in
flakes like snow and burning up mountains and plains and other lands,
with men and women; and then arose vast masses of smoke; and whosoever
beheld this died within the space of half a day..." There seems little
doubt also that a worldwide cooling of the Earth played a fundamental
part in the process. The Arctic polar cap extended, changing the
cyclonic pattern and leading to a series of disastrous harvests. These
in turn led to widespread famine, death and social disruption.

In England and Scotland there is a pattern of abandoned villages and farms, soaring wheat prices and falling populations.

In Eastern Europe there was a series of winters of unparalleled
severity and depth of snow. The chronicles of monasteries in Poland and
Russia tell of cannibalism, common graves overfilled with corpses, and
migrations to the west.

Even before the Black Death came, then, a human catastrophe of great
proportions was under way in late medieval times. Indeed the cold snap
lasted well beyond the period of the ... plague. A number of such
fluctuations are to be found in the historical record, and there is
good evidence that these climatic stresses are connected not only with
famine but also with times of great social unrest, wars, revolution and
mass migrations.

In spite of their traumatic effects, these global coolings probably
amounted to no more than about a degree in average summer temperatures
as compared with today: even relatively minor climatic effects have had
a profound influence on human history. A major climatic cooling
amounting to several degrees. With the modern dependence on 'green
revolution' crops, finely tuned to give a high yield under a narrow
range of climatic conditions, the onset of such a 'winter' would cause
the population of the world to crash in the course of a decade, or even
a single year. Such events are completely outside normal experience and
their existence is not generally recognized, even though they represent
a hazard vastly more horrific than any of the more familiar
catastrophes such as earthquake, famine or flood. ... More to the point
though, civilization is in the presence of a hitherto unrecognized
cosmic phenomenon which could plunge it without warning into a Dark Age.

What can be done?

Unfortunately the extent and epoch of the next cosmic winter depend
for the moment on a number of imponderables which lie outside the scope
of existing knowledge: it is not now possible to make an accurate
assessment of what the future has in store. This is clearly not a
satisfactory state of affairs. Nor can we expect that Nature will hold back on account of our ignorance or lack of preparedness.However, in view of the seriousness of cosmic winters for human
survival, and noting the vast expenditures to the tune of many billions
of dollars on a whole variety of preparations for all manner of lesser
hazards and calamities, both man-made and natural, disease and nuclear
war not excluded, one must surely note also that not a single cent of taxpayer' money is currently devoted to their study. [...]

The first step must therefore be one of exploration. An asteroid in
a Taurid orbit, carrying 100,000 megatons of impact energy, coming out
of the night sky, would be visible in binoculars for about six hours
before impact. By the time it was a naked-eye object it would be at
most half an hour from collision. In its final plunge it would be seen
as a brilliant moving object for perhaps 30 seconds. One needs more
time than this to prepare for the [Cosmic] Winter. A thorough
exploration of the Earth's surroundings, and the discovery and tracking
of probably tens of thousands of bodies, is therefore a first
requirement. This is technically feasible.

Complementing such an observational programme, a fresh exploration
of the past, armed now with the new astronomical understandings, is
also necessary; not just for its own sake but also to arrive at a
better understanding of the risks. .[...]

To go from mere statistical projection to detailed forecasting,
then, a generation of exploration, both of the Earth's environment and
of our history and prehistory, will be necessary. As we have remarked,
such studies cannot be seen only as an academic game: there is nothing academic about a 1,000 megaton impact, and the modern prospects for nuclear error, not to mention nuclear meltdown, exacerbate the issue.

And if the sirens should sound, what then? It may be marginally
within the capacity of present day technology to divert a small
asteroid, given enough warning, though not a swarm of them... But at
least, unlike our forebears, we have a chance to act: we need no longer
be helpless in the hands of the gods. The main problem at the moment is to be aware that there is a problem.

Three thousand years ago, in accordance with age-old practice, the
kings of Babylon were still employing astronomer-priests to give
warnings of cosmic visitations. A thousand years ago, the emperors of
China were still relying on similar skills, while in Europe the Pope
saw messages in the sky and urged Holy War. But this latter was an
aberration; for the last two and a half thousand years have seen the
decline and fall of the sky gods, and the growing presumption that the
cosmos is stable and regular. The shift of paradigm has been
unconscious, convenient, insidious and thorough. Probably, the
rediscovery of a lost tradition of celestial catastrophe could not have
been made through analysis of ancient texts alone; a key had to be
provided, and it has been, by the paraphernalia of modern science. It
is a salutary lesson both on the capacity of human reasoning to get it
wrong for long periods of time, and on the essential unity of knowledge.

It would be naïve to think, however, that one merely has to point to
deep-seated cracks in the structure of modern knowledge to have
scholars setting to and constructing a better framework within which
mankind might plan his future. There is considerable
intellectual capital invested in the status quo, enough to ensure that
those with an interest in preserving it, the 'enlightened' and the
'established', will continue to present the cosmos to us in a suitably
non-violent form. The history of ideas reveals that some will even go further and act as a kind of thought police,
whipping potential deviants into line. For them, temporal power takes
precedence over the fate of the species. (Clube, The Cosmic Winter)

Famed astronomer, Fred Hoyle, friend and colleague of Clube, made
some interesting remarks in his book: "The Origin of the Universe and
the Origin of Religion" along the same lines.

Science is unique to human activities in that it possesses vast
areas of certain knowledge. The collective opinion of scientists in
these areas about any problem covered by them will almost always be
correct. It is unlikely that much in these areas will be changed in the
future, even in a thousand years. And because technology rests almost
exclusively on these areas the products of technology work as they are
intended to do.

But for areas of uncertain knowledge the story is very different.
Indeed the story is pretty well the exact opposite, with the collective
opinion of scientists almost always incorrect.

There is an easy proof of this statement. Because of the large
number of scientists nowadays and because of the large financial
support which they enjoy, uncertain problems would mostly have been
cleared up already if it were otherwise. So you can be pretty certain
that wherever problems resist solution for an appreciable time by an
appreciable number of scientists the ideas used for attacking them must
be wrong.

It is therefore a mistake to have anything to do with popular ideas for solving uncertain issues, and the more respectable the ideas may be the more certain it is that they are wrong. [...]

Another big one for the book is the origin of life, which according
to respectable opinion happened here on the Earth. Imagine the Earth's
history to be represented by a single day. Then the origin of life did
not occur in the last 20 hours because there is fossil evidence that
life has existed over the last 20 hours. Nor did life originate in the
first 3 1/2 hours, because in this early period the Earth was so
heavily bombarded by missiles from outside that even rocks were
pulverized so violently as to be unable to preserve their integrity. So
life, if it originated on the Earth, did so between 03:30 a.m. and
04:00 a.m. We therefore ask for the evidence that the amazing
biochemical miracle of the origin of life happened in this
comparatively brief window in the Earth's history. A few sedimentary
rocks have survived from it, but they have unfortunately been heated so
much that any fossil evidence of life and its origin which might have
existed have been lost. Thus the evidence for the respectable popular
belief is nil.

This is one remarkable aspect of the popular belief, that it is founded on nothing.

The other remarkable aspect is the intensity of the opprobrium one
incurs if one denies it. Only a little biochemical knowledge is needed
to see this is yet another situation to set the cats in an uproar.

Biology is replete with them. We are told that natural selection
acts to spread small advantageous mutations and operates to suppress
disadvantageous bones. But small changes must be frequent if a species
is to go anywhere much, in which case the bad and the good are
superposed on each other, and how then does natural selection manage to
separate them? With the bad generally accepted to be more frequent than
the good, all natural selection can do, in simple replicative systems
at any rate, is to minimise the rate at which things get worse.

You would think this problem would have been addressed with some care, but as far as I can see it never is. The fossil record of the last 500 millions years provides a serious indictment of biological thinking on evolution.It provides ample evidence of small changes and little or none of big
changes. So if evolution is correct, as I suspect it to be, the big
changes occur swiftly and the small changes slowly, the big changes so
swiftly that they cannot be captured by the random moments revealed by
the fossil record. As a physicist might put it, evolution takes place
through a sequence of delta-functions, not smoothly as according to
respectable scientific academies it is supposed to do.

More than a century ago Alfred Russell Wallace noticed that the higher qualities of Man are acausal, like the Universe itself. Where
human qualities have been honed by evolution and natural selection
there is very little difference between one individual and another. Given
equivalent opportunities for training, healthy human males of age 20
will hardly differ in their abilities to run at pace by more than 10
percent between the Olympic runner and the average.

But for the higher qualities it is very much otherwise.From enquiries among teachers of art, Wallace estimated that for every
child who draws instinctively and correctly there are a hundred that
don't. The proportions are much the same in music and mathematics. And
for those who are outstanding in these fields the proportions are more
like one in a million. Having made this point Wallace then made the
striking argument that, while the abilities with small spread like
running would have been important to the survival of primitive man, the
higher qualities had no survival value at all.

Perhaps this is not entirely true? Perhaps "higher abilities" had
survival value in terms of those individuals who could "read the
handwriting on the wall" in a scientifically observational way? Or,
more speculatively, perhaps higher abilities could ensure survival by
warning an individual that catastrophe was on its way thereby enabling
them to act in preparation to survive?

Over a span of 12 years spent in the Amazon and in
the forests of the East Indies, Wallace is said to have discovered
30,000 new species off his own bat. He lived by shipping his specimens
to an agent in London who then marketed them to museums. During most of
the time, when he wasn't writing epoch-making papers on biological
evolution, he lived with primitive tribesmen. Wallace therefore knew a
great deal about the modes of survival of primitive man, probably more
than anybody else of his generation and probably more than anybody does
today. His views on the matter therefore carry weight. What he said was
that in his experience he never saw a situation in which an aptitude for mathematics would have been of help to primitive tribes. So little numerate were they that in 12 years he saw only a few who could count as far as 10.

His conclusion was the higher qualities, the
qualities with large variability from individual to individual, had not
been derived from natural selection.

Abilities derived from natural selection have small spread. Abilities not derived from natural selection have wide spreads.

[...]

I think the higher qualities must be of genetic origin, the
same as the rest. The mystery is that we have to be endowed with the
relevant genes in advance of them being useful. The time order
of events is inverted from what we would normally expect it to be, a
concept that is of course gall and wormwood to respectable opinion. The
objection is that it explodes one's concepts, raising all manner of new
ideas. Which is exactly what respectability dislikes, because it is
only in times of stagnation that respectability flourishes.[...]

Already in 1813, in a lecture to the Royal Society of London,
William Wells described the process of evolution by natural selection.
In the early 1830's it was being asked how this process might go in
detail. Could it explain evolution on a large scale, as in the
well-known picture of evolution occurring like a branching tree?
General opinion was that it could not, and for a reason that was good
and which was never answered in the enthusiasms of the later Darwinian
movement.

It was observed that plants and animals always, or almost always,
have limited habitats, usually with quite sharp boundaries in which
they thrive and outside which they do not.

Why, if evolution could produce very large differences like
those between horses, bears and primates, could it not produce the much
smaller differences that would serve to enable species to extend their
limited habitants?

Why did each species not have the plasticity (as it was called) to
spread itself all over the world? The fact that this emphatically was
not what happened suggested that, while by selection each
species fine-tuned its abilities within the range accessible to it, the
range in every case is small, far smaller than would be needed to
produce the difference between horses and bears. (Hoyle, The Origin of the Universe and the Origin of Religion)

Hoyle's remarks quoted above certainly raise a lot of questions, but
the one that immediately comes to my mind is: are human beings with
"higher faculties" mutations? A related question might also be: are
psychopaths also mutations in the other direction? But I don't want to
divert onto that topic just yet, we'll save it for another article.
Again, I want to reiterate what I wrote in the previous article:

If short-period bombardment of our planet by comets or comet dust is
a reality (as it increasingly appears to be); and the effects of such
an event are deleterious in the extreme; and if we are in fact overdue
for a repeat performance of such a visitation (which also appears to be
the case); what effect might public awareness of this have on the
status quo on the planet at present? Would the bogus "war on terror"
not become instantly obsolete and would people across the planet not
immediately demand that their political leaders reassess priorities and
take whatever action possible to mitigate the threat? And if those
political leaders refused to do so and it became known that that this
grave threat to the lives of billions was long-standing and common
knowledge among the political elite (with all that that implies), what
then? Revolution? One last hurrah before the 6th extinction?

Who knows. We only know that this knowledge, in its fullest
explication, is being suppressed and marginalized. The reasons for the
psychological games and ploys may be interesting to investigate. so
that is what we will look at next: Why is Humanity so Deaf, Dumb and
Blind?

Very large collisions in the asteroid belt could lead temporarily to
a substantial increase in the rate of impacts of meteorites on Earth.

Orbital simulations predict that fragments from such events may
arrive considerably faster than the typical transit times of meteorites
falling today, because in some large impacts part of the debris is
transferred directly into a resonant orbit with Jupiter1, 2. Such an
efficient meteorite delivery track, however, has not been verified.
Here we report high-sensitivity measurements of noble gases produced by
cosmic rays in chromite grains from a unique suite of fossil
meteorites3 preserved in approx480 million year old sediments. The
transfer times deduced from the noble gases are as short as approx105
years, and they increase with stratigraphic height in agreement with
the estimated duration of sedimentation. These data provide powerful
evidence that this unusual meteorite occurrence was the result of a
long-lasting rain of meteorites following the destruction of an
asteroid, and show that at least one strong resonance in the main
asteroid belt can deliver material into the inner Solar System within
the short timescales suggested by dynamical models.

The terrestrial and lunar cratering rate is often assumed to have
been nearly constant over the past 3 Gyr. Different lines of evidence,
however, suggest that the impact flux from kilometre-sized bodies
increased by at least a factor of two over the long-term average during
the past approx100 Myr.

Here we argue that this apparent surge was triggered by the
catastrophic disruption of the parent body of the asteroid Baptistina,
which we infer was a approx170-km-diameter body
(carbonaceous-chondrite-like) that broke up 160 (+30/-20)Unfortunately
we are unable to provide accessible alternative text for this. If you
require assistance to access this image, or to obtain a text
description, please contact npg@nature.com Myr ago in the inner main
asteroid belt. Fragments produced by the collision were slowly
delivered by dynamical processes to orbits where they could strike the
terrestrial planets. We find that this asteroid shower is the most
likely source (>90 per cent probability) of the Chicxulub impactor
that produced the Cretaceous/Tertiary (K/T) mass extinction event 65
Myr ago.

The rise and diversification of shelled invertebrate life in the
early Phanerozoic eon occurred in two major stages. During the first
stage (termed as the Cambrian explosion), a large number of new phyla
appeared over a short time interval approx540 Myr ago. Biodiversity at
the family, genus and species level, however, remained low until the
second stage marked by the Great Ordovician Biodiversification Event in
the Middle Ordovician period.[1, 2, 3]

Although this event represents the most intense phase of species
radiation during the Palaeozoic era and led to irreversible changes in
the biological make-up of Earth's seafloors, the causes of this event
remain elusive. Here, we show that the onset of the major phase of
biodiversification approx470 Myr ago coincides with the disruption in
the asteroid belt of the L-chondrite parent body - the largest
documented asteroid breakup event during the past few billion years[4,
5]. The precise coincidence between these two events is established by
bed-by-bed records of extraterrestrial chromite, osmium isotopes and
invertebrate fossils in Middle Ordovician strata in Baltoscandia and
China. We argue that frequent impacts on Earth of kilometre-sized
asteroids - supported by abundant Middle Ordovician fossil meteorites
and impact craters[6] - accelerated the biodiversification process.

Introduction

Evidence for an early Palaeozoic major asteroid breakup was already
established in the 1960s when recent ordinary chondrites of the L type
were shown to commonly have K - Ar gas retention or shock ages of about
450 - 500 Myr (refs 4,5). About 20% of the meteorites reaching Earth
today are shocked L chondrites from this event. The finds of more than
50 fossil L-chondritic meteorites (1 - 20 cm in diameter) in Middle
Ordovician limestone in southern Sweden show that the meteorite flux
was enhanced by one to two orders of magnitude for at least a few
million years after the disruption event[6, 7]. The L-chondritic origin
of the fossil meteorites is demonstrated by element and oxygen isotope
analyses of relict chromite grains as well as by petrographic studies
of chondrule textures[6, 7, 8]. Chromite is the only common mineral in
chondrites that survives extensive weathering on the wet Earth surface.
In the limestone beds containing common meteorites, abundant chromite
grains from decomposed meteorites and micrometeorites are also found[9,
10, 11]. Cosmic-ray-induced 21Ne in chromite from the fossil meteorites
increases upwards in the strata, supporting a common origin from an
asteroid breakup event[12]. High-precision 40Ar-39Ar dating of recent L
chondrites has constrained the timing of their parent-body disruption
to 470 plus/minus 6 Myr ago, which is identical within uncertainties to
the age of 467.3 plus/minus 1.6 Myr ago for the beds with fossil
meteorites according to the latest geologic timescale[13].

During the Great Ordovician Biodiversification Event (GOBE), in the
Middle to Late Ordovician, biodiversity at the family level increased
from a Phanerozoic all-time-low in the Cambrian and Early Ordovician to
levels approximately three times higher in the Late Ordovician[1, 2, 3,
14, 15] (Fig. 1). The new biodiversity levels of marine life were
matched by an increase in biocomplexity, and were sustained until the
end of the Palaeozoic except for short-term declines in connection with
extinction events in the latest Ordovician and Late Devonian periods.
The GOBE generated few new higher taxa, for example phyla, but
witnessed a staggering increase in biodiversity at, for example,
species level among a wide variety of groups of skeletal
invertebrates[2, 3, 15]. Diagrams of changes in global or regional
biodiversity during the GOBE give only a crude representation of the
timing and pace of the faunal change[15, 16]. The global signal
represents a combination of many regional diversity changes across a
range of fossil groups[2, 3]. The most focused global compilation
through the early Palaeozoic, shown in Fig. 1, demonstrates a sharp
rise in biodiversity at about the Arenig - Llanvirn boundary (about 466
Myr ago). This signal is evident across a number of groups, such as the
brachiopods, cephalopods and echinoderms, but less clear in some
members of the Cambrian fauna (trilobites) and the modern fauna
(gastropods)[15]. It also corresponds to the second-cycle diversity
peak in conodonts recognized by Sweet[17]. The causes of the GOBE, and
its relation to both intrinsic (biological) and extrinsic
(environmental) factors are not known2. Many authors have suggested a
link to increasing levels of atmospheric oxygen, favouring the
radiation of aerobic metazoan life together with an expansion of the
phyto and zooplankton[18, 19].

Although this diagram from Sepkoski gives a good representation of
the overall biodiversity trend, the resolution is too crude for
correlation with field data. Trem.=Tremadocian (Global) and Tremadoc
(British), Ash.=Ashgill, Lland.=Llandovery, We.=Wenlock, Lud.=Ludlow,
F.=Floian, Dap.=Dapingian, Sand.=Sandbian, H.=Hirnantian.

----

Although biodiversity diagrams such as in Fig. 1 show the broad
outline of change, at a higher resolution they suffer from the effects
of poor correlation and poor preservation of faunas, focus on a
particular horizon or group of fossils and data binning. To relate
biological change to physical events, detailed high-resolution
multiparameter records across complete and fossil-rich sections are
required. Here, we have constrained the precise stratigraphic level for
the L-chondrite disruption event by searches for sediment-dispersed
extraterrestrial (chondritic) chromite grains and Os isotopic studies
in Middle Ordovician sections with condensed limestone (Fig. 2). These
results are matched by the most detailed bed-by-bed studies of the
distribution of brachiopod species across Middle Ordovician strata in
Baltoscandia (Fig. 3) conducted until now.

Results are shown for sections at Kinnekulle (Hällekis and Thorsberg
quarries) and southern Scania (Killeröd and Fågelsång sections), 350 km
apart in southern Sweden, and the Puxi River and Fenxiang sections, 4
km apart in south-central China. The distribution of Os isotopes across
the Hällekis section is also shown. The stratigraphic interval yielding
abundant fossil meteorites in the Thorsberg quarry is indicated6. The
conodont biostratigraphy shown has been produced specifically for this
study, using consistent taxonomic concepts for the different sections. M. ozarkodella=Microzarkodinaozarkodella.

The results are based on bed-by-bed collections at eight
localities[22]. Note the dramatic increase in biodiversity (black line)
and high extinction (blue line) and origination (red line) levels
following the regional Volkhov - Kunda boundary, that is, the same
level where extraterrestrial chromite appears and Os isotopes change in
Fig. 2. B. triang.-navis=Baltoniodustriangulatus-navis. The dashed lines show the boundaries between the regional states.

----

The sections studied for extraterrestrial chromite grains occur at
Kinnekulle and in southern Scania, 350 km apart in southern Sweden, and
at Puxi River (Puquie) and Fenxiang, 4 km apart in south-central China
near Yichang, Hubei province. The extraterrestrial chromite grains
(>63 mum) have been retrieved from about 10 - 30-kg-sized limestone
samples that were dissolved in HCl and HF acid[10]. The
extraterrestrial chromite can be readily distinguished from terrestrial
chromite by its distinct element composition[6, 10]. The results of the
extraterrestrial chromite searches are shown in Fig. 2 and in the
Supplementary Information. In the section studied in greatest detail,
at Kinnekulle, in 379 kg of limestone from 14 levels across 9 m of
strata below the Lenodus variabilis zone, only 5
extraterrestrial chromite grains were found[10 ](Fig. 2). The values
then increased dramatically to typically 1 - 3 extraterrestrial
chromite grains per kilogram of rock in the L. variabilis, Yangtzeplacognathus crassus and Microzarkodina hagetianazones. In this interval, a total of 332 extraterrestrial chromite
grains were found in 174 kg of rock. In southern Scania and in China,
the distribution trends of extraterrestrial chromite grains are very
similar to that at Kinnekulle. In southern Scania, some beds in the L. variabiliszone contain up to 6 extraterrestrial chromite grains per kilogram of
rock, whereas only 2 grains were found in 125 kg in the beds spanning 7
m below[11]. In the Chinese sections, 89 kg of limestone below the L. variabiliszone yielded only 1 extraterrestrial chromite grain compared with 117
extraterrestrial chromite grains in 89 kg in the overlying beds (Fig.
2).

The first appearance of common extraterrestrial chromite grains in the lower L. variabiliszone in the three sections is a strong indication of the precise timing
of the disruption of the L-chondrite parent body. The data also
represent strong support for an increase by two orders of magnitude in
the flux of micrometeorites and meteorites to Earth following the
disruption event, as previously suggested on the basis of studies of
the Swedish sections alone[9, 10, 11]. There is no indication that
changes in sedimentation rates, on average a few millimetres per
thousand years, can explain the observed major trend in
extraterrestrial chromite concentrations, although individual beds may
have formed at different rates. That the disruption event occurred in
the lower L. variabilis zone is consistent with
cosmic-ray-induced 21Ne ages of chromite grains from the fossil
meteorites[12]. In 5 - 10-Myr-old younger condensed limestone in the
Gärde quarry, central Sweden, we found 9 extraterrestrial chromite
grains in 23 kg of rock. This indicates that the extraterrestrial
chromite flux is still enhanced compared with that before the asteroid
breakup. The low pre-breakup concentrations of extraterrestrial
chromite grains are similar to concentrations measured in similarly
condensed sediments from much younger periods. For example, in 210 kg
of pelagic limestone (average sedimentation rate about 2.5 mm kyr-1)
from the famous Late Cretaceous - Paleocene Gubbio section in Italy we
found only 6 extraterrestrial chromite grains[20].

Our analyses of 187Os/188Os ratios in whole-rock limestone samples
through the Kinnekulle section show a relatively stable trend with
ratios around 0.6 - 0.8 through the lower 11 m of section, but from the
same bed where the extraterrestrial chromite grains become common and
further up, ratios mainly lie in the range 0.3 - 0.5 (Fig. 2; Supplementary Information).
The simplest explanation for this prominent change is an increasing
influence of an extraterrestrial component (187Os/188Os approx 0.12) at
the expense of a detrital/hydrogenous Os component (187Os/188Os approx
0.8) (ref. 21), well in line with conclusions based on extraterrestrial
chromite trends.

Some of the best sections for studies of Ordovician invertebrate
diversification occur in Baltoscandia[22]. We have established the
Middle Ordovician biodiversity trends for brachiopods on the basis of
bed-by-bed sampling of more than 30,000 fossils from 8 sections in
Baltoscandia (Fig. 3). The phylum Brachiopoda dominated the benthos of
the Palaeozoic evolutionary fauna both in abundance and diversity and
formed a pivotal part of the suspension-feeding food chains of the era.
The phylum was widely dispersed across shallow to deep-water
environments around all of the palaeocontinents. We show here that
there are two intervals in the succession when the Baltoscandian
brachiopod fauna suffered dramatic changes - one within the lower part
of the regional Volkhov stage and one at the base of the Kunda stage
(Fig. 3). The largest change occurs during exactly the same interval
when the L-chondritic extraterrestrial flux peaks at the base of the
Kunda stage, and when brachiopods more typical of the Palaeozoic
evolutionary fauna, that is, orthides and strophomenides, diversified.

Modelling studies suggest an enhanced flux of extraterrestrial
matter, including large asteroids, during 10 - 30 million years after
major asteroid disruption events[23]. The L-chondrite parent-body
breakup at 470 Myr ago is thought to have created the Flora family of
asteroids[24]. These asteroids were particularly prone to enter
Earth-crossing orbits because of their position relative to an
important orbital resonance[23, 24]. Apparently, the Middle Ordovician
interval with enhanced extraterrestrial flux is broadly coincident with
the main phase of the GOBE[1, 2, 3, 15]. At least in Baltoscandia, the
onset of the two events seems to coincide precisely (Figs 2, 3). Albeit
speculative, the best explanation for the coincidence is that frequent
impacts on Earth of large asteroids, fragments of the L-chondrite
parent body, generated changes in the biota. Impact-related
environmental perturbations may have accelerated a process driven also
by intrinsic biological mechanisms. Although much contemporary research
has focused on the negative effects of large impacts, such as in the
Cretaceous - Tertiary boundary case[25], more minor and persistent
impacts could generate diversity by creating a range of new niches
across a mosaic of more heterogeneous environments. Such diversity
increases are predicted by the well-established intermediate
disturbance hypothesis, initially applied to diversity changes in coral
reefs and tropical rainforests[26]. Frequent impacts may also have
destabilized ecological communities, allowing invasive species to take
over and displace incumbent communities. The ecological and taxonomic
amplitudes of the Middle Ordovician biodiversification may be decoupled
and there are important feedback loops in the process. This phase of
the diversification is marked by a brachiopod takeover from trilobites
in benthic communities, and the establishment of recumbent life modes
and size increases in many brachiopod clades. However, in contrast to
the carnivores and detritus feeders of the modern fauna, the Palaeozoic
fauna was then dominated by a suspension-feeding benthos with low
metabolic rates better equipped to deal with and benefit from major
environmental disruptions.

There are about 170 known impact craters on Earth and their record
shows that impacts may have been more common by a factor of 5 - 10
during the Middle Ordovician compared with other periods of the
Phanerozoic[6, 13]. Four of seventeen known impact craters in
Baltoscandia (Granby, Lockne, Kärdla and Tvären craters) are of Middle
to early Late Ordovician age. For only very few of Earth's craters has
it been possible to determine the impactor type, but for at least the
458-Myr-old Lockne crater in central Sweden, chromite in resurge
deposits has implicated an L-chondritic impactor[27].

The strata in China and Baltoscandia that we show are rich in fossil
meteorites and/or extraterrestrial chromite grains have long been known
to include horizons with unusual lithologies. Over several hundred
thousand square kilometres in southern Sweden, the succession of
homogeneous red orthoceratite limestone is interrupted by a 1-m-thick
anomalous grey, clay-rich interval with a peculiar fauna. During
deposition of this bed, centimetre-sized cystoids seem to have
literally covered the sea floor of a major part of the Baltic Basin. In
west Russia, peculiar ooid horizons characterize the interval, and in
China, unusual mini-mounds interrupt the normal succession of nodular
marl and limestone[28] (Fig. 2). The possible relationship of these
anomalous lithologies and structures to asteroid impacts or other
astronomical perturbations, such as Solar System gravity disturbances,
certainly warrants further studies. As shown here, at least on a
regional scale, there is a close temporal coincidence between major
biological change and the disruption of the L-chondrite parent body.

Recently, the impactor at the Cretaceous - Tertiary boundary has
been tied by modelling to an asteroid disruption event at 160 Myr ago
(ref. 29), but this event may not have led to a pronounced asteroid
shower as focused in time as the one in the Middle Ordovician, and it
has not left any obvious signal in the collision history of present-day
meteorites.

Methods

For chromite searches, samples of typically 10 - 30 kg of limestone
were crushed and decalcified first in 6 M HCl and then in 18 M HF at
room temperature. The acid-insoluble fraction, 63 - 355 mum, was
searched for opaque minerals under the binocular microscope. Picked
grains were mounted in epoxy resin and polished to a flat surface using
a 1 mum diamond slurry. Element analyses were carried out with a
scanning electron microscope - energy dispersive spectrometer[9, 10,
11, 27]. The extraterrestrial chromite grains are characterized first
by high Cr2O3 contents of approx55 - 60 wt%, FeO concentrations in the
range of approx25 - 30 wt%, low Al2O3 at approx5 - 8 wt% and MgO
concentrations of approx1.5 - 4 wt%. The most discriminative feature,
however, is narrow ranges of V2O3, approx0.6 - 0.9 wt%, and TiO2,
approx2.0 - 3.5 wt%, concentrations. For a grain to be classified as an
extraterrestrial chromite grain, it has to have a composition within
the defined ranges for all elements listed[10].

For Os analyses, whole-rock limestone samples were ground in an
agate mortar. Between 3 - 10 g of powdered sediment was weighed, mixed
with an isotopically enriched spike containing 190Os, dried at room
temperature over night and then mixed with borax, nickel and sulphur
powder. After fusing the mixture for 90 min at 1,000 °C, the NiS bead
was separated and dissolved in 6.2 M HCl and the residue filtered at
0.45 mum. Insoluble platinum-group-element-containing particles were
dissolved in concentrated HNO3 in a tightly closed Teflon vial at
approx100 °C. After dissolution, the Teflon vial was chilled in ice
water to minimize the escape of volatile OsO4. Osmium was then
extracted from this vial with the sparging method directly into the
torch of a single-collector inductively coupled plasma mass
spectrometer (Finnigan Element). Typical Os blanks are <1 pg g-1.
Depending on the Os concentration, the precision in 187Os/188Os is
between 0.5% and a few per cent. The details of the method and an
evaluation of the accuracy and precision of the data have been
published elsewhere[30].

Acknowledgements

This study was supported by financial support to B.S. from the
National Geographic Society, Swedish Research Council (VR) and Crafoord
Foundation and to D.A.T.H. from the Carlsberg Foundation. This is a
contribution to International Geological Correlation Programme project
503.

In the 5 million years or so that it took for
apes to become human, many human-like branches of the evolutionary tree
were lopped off. Scientists have long wondered why these other hominid
species, estimated to number a dozen or more, didn't make it.

Were those who came to travel to the Moon and ponder their very
origin the logical and inevitable victors in the most important of all
Darwinian struggles?

Or did we just get lucky?

A newly presented mathematical argument suggests that the birth of
Homo sapiens was guided by catastrophic asteroid or comet impacts,
which created climate conditions that competing species, frankly,
couldn't handle.

It also holds that our human ancestors avoided early elimination by the statistical skin of their rotting teeth.

"The reason that Homo sapiens have survived in spite of these global
disasters has little to do with the traditional explanations given by
neo-Darwinists," said Benny Peiser, a social anthropologist at
Liverpool John Moores University. "It is sobering to realize that we
are alive due to cosmic luck rather than our genetic makeup."

Peiser bases his argument on the fact that populations of hominids
and early modern humans were extremely small. "Had any of these impacts
occurred in the proximity of these population groups, we might also
have gone the way of the dodo," he said.

The study's assumptions and calculations have met with strong
caution and even sharp criticism among scientists who specialize in
evolution, as well as asteroid experts.

Adaptive advantage

David Balding, a professor of applied statistics at University of
Reading in the U.K., said the idea that human survival is due to
"cosmic luck" does not compute:

"Perhaps we were lucky in avoiding a massive impact, but perhaps it
was our adaptive advantage that helped us survive modest regional
impacts whereas our hominid cousins did not," said Balding, whose own
research focuses on human evolution.

But some called the new scenario plausible. It has not been
published in a peer-reviewed journal but it is based on impact
estimates that are generally accepted by the asteroid research
community, though there are disagreements over the precise number of
times a large asteroid or comet has struck our planet.

Peiser laid the idea out earlier this month at a conference,
"Celebrating Britain's Achievements in Space." He worked with Michael
Paine, a volunteer for the Planetary Society in Australia who ran
impact scenarios through a computer program. (Paine has written
freelance stories for SPACE.com in the past.)

The researchers concluded that there would have been 20 "globally
devastating" impacts during the past 5 million years, with effects
strong enough to have had "a catastrophic and detrimental effect" on
human evolution. Five million years ago is roughly the time when
hominids diverged from other apes, though some recent controversial
evidence puts the split as far back as 6 million years ago.

Did space rocks set the human stage?

No one argues that asteroids can be devastating when they tangle
with Earth. An impact 65 million years ago is widely believed to have
spurred the demise of the dinosaurs and many other animals and plants.

But efforts to tie other, more ancient mass extinctions to impacts
remain inconclusive. While extinctions are clearly identifiable in
fossil records, impact evidence seems not to survive the millennia as
well. So impact estimates are based largely on the Moon -- a nearby
archive of countless craters that have not eroded much over time.

Still, because scientists have not witnessed a severe impact, the presumed effects are speculative.

If an asteroid larger than a kilometer (0.6 miles) hit the planet,
it would cause instant death across a wide area near the site of
impact, and researchers generally agree that drastic climate changes
could last a year or more. Even our protective ozone layer could be
damaged, studies have shown.

But the precise consequences of these effects are not known. It is
thought that long-term climate change could make life impossible for
many species, which in turn would cause mass death that might move up
entire food chains.

Peiser suggests another possible effect: "The abrupt loss of the
ozone layer and the sudden release of toxins may even affect the DNA in
some unknown manner, thus triggering macro-mutations, including the
sudden reorganization of entire genomes."

Ellen Thomas, a Wesleyan University research professor who examines
how climate change affects evolution, said few evolutionists would by
this argument of quick, significant changes in the genetic blueprints.
Instead, macro-mutations are seen by many as a genetic dead end.

"Macro-mutations can hardly ever lead to evolution," Thomas said. "They lead to non-viable organisms."

Basic numbers questioned

Of course to affect human evolution in any fashion, a space rock
first has to hit Earth. But "no one knows how many impacts took place,
or when, or with what severity, over the past 5 million years," said
David Morrison, an asteroid expert at NASA's Ames Research Center in
California.

Morrison told SPACE.com that instead of the 20 potentially
devastating impacts assumed by the study, he expects there were
probably only five or 10 with enough energy to create global
environmental effects.

"But we know very little about specific impacts in this time frame,
and virtually nothing at all about their actual environmental effects,"
Morrison said, adding that there is "no evidence of an impact
associated with a hominid extinction."

Morrison did not discount the whole idea, however.

"I would be surprised if impacts had not had some influence on early
hominid populations and perhaps evolution," he said. "On the other
hand, I am not convinced that impacts led to numerous extinctions in
the past 5 million years. This is all interesting speculation, but
specific data are lacking on either impacts or extinction events and
there is no known correlation between the two."

Peiser counters that the estimates used in the study are "very
conservative." He acknowledges that shortcomings in the human fossil
record (fossils on land erode more easily than those in the oceans)
"are far too big to allow any direct correlation between impact
catastrophes and hominid extinction." But he said that the study shows
that "impact catastrophes that occurred during the crucial period of
human evolution should no longer be ignored."

Still, it is clear that more research will be needed before any consensus emerges.

"What [Peiser and Paine] may have added," said Balding, the
statistics professor, "is some quantitative simulations to make more
precise some well established speculations."

Speculation about evolution is nothing new. And the more one delves
into the nitty-gritty of our own past, the stronger the criticism gets
over Peiser's attempt to reinvent Darwin.

Does Darwin need reinventing again?

If asteroid experts are sometimes a mile apart on their view of
history -- and they are -- then evolutionary theorists live on
different continents.

Followers of Charles Darwin have long believed that failed branches
of our ancestry reflect a common mode of evolution, whereby species are
gradually replaced by more advanced species that adapted because of
their superior genetic fitness.

But in recent decades, a different view called punctuated equilibria
has taken hold. This theory, first put forth in the 1970s by Stephen J.
Gould and Niles Eldredge, expects sharp changes in evolution.

In either scenario, luck plays a role. And both fit within the most
famous of Darwinian themes, survival of the fittest. But the rapid
shifts assumed in punctuated equilibria, be they caused by sudden
disasters or other means, are thought to be the mechanism by which one
species replaces another.

"There has been debate for over 100 years on whether evolution is gradual or punctuated," said Balding.

And the debate continues. Recent fossil findings have some
researchers leaning back toward the gradual approach to human evolution.

Peiser said his study supports punctuated equilibria, and helps
explain why "almost all hominids, i.e. the 14 known species of human
ancestors, have become extinct during the last 5 million years."

But Wesleyan's Ellen Thomas said it is not even known that there were 14 species.

"The human fossil record is incomplete, and it is not easy to agree
on which fossils belong to different species," Thomas said in an e-mail
interview. "The experts disagree wildly."

Thomas echoed other scientists in pointing out that there is no
fossil evidence -- neither of human remains in Africa nor marine
organisms, which leave a much more complete record -- that reveal any
mass die-offs during the 5 million-year period covered in Peiser's
study.

"And if the extinctions affected humans, they should show up in the
extinction record of other organisms as well," Thomas said. "The paper
just shows that many impacts, many of which could have been damaging,
possibly occurred."

But Peiser argues that no expert on near-Earth asteroids, the space
rocks known to exist in our region of the solar system, questions that
"many such global disasters must have occurred." Yet he said "all
textbooks on human evolution completely ignore the occurrence of
catastrophic impacts."

Other forces of evolution

While Peiser and Paine suggest that comets or asteroids are a
driving force behind evolutionary change, it is the climatic
consequences of impacts that are the would-be crushing mechanisms for
fledgling species. Other researchers have long debated possible links
between climate change and human evolution.

For example, cold periods are suspected of forcing migrations that
created small, isolated groups that could have evolved significantly
but then died out. One such period may have occurred as recently as
71,000 years ago. But firm links between climate and serious
evolutionary changes elude researchers.

One recent international study, released earlier this year and led
by Jeremy Marlow of Newcastle University, showed evidence of a
significant cooling of the climate 2 million years ago that the authors
said "adds weight to the theory that climate change played a
significant part in the evolution of early humans."

Further clouding the possibilities, recent findings have hinted at
the possibility that the worst extinctions might require multiple
killing mechanisms, such as when an impact, or perhaps several, happens
to occur during a time of heavy volcanic activity.

Irony in our existence

In an ironic preface to the whole argument, it's possible that
asteroids and comets were responsible for life in the first place. A
growing movement among astrobiologists suggests that rocks from space
brought critical building blocks that stimulated the initial biological
activity in the earliest primordial soup billions of years ago.

But regardless of whether cosmic messengers helped make us who we
are, there is one thing researchers seem to agree on: Given the
evidence that our ancient ancestors were clustered in a relatively
small area (in Africa) you are somewhat lucky to be reading about all
this.

"Asteroids certainly had the opportunity to wipe out man at his
roots," said Jack G. Hills, an asteroid specialist at Los Alamos
National Laboratory. "Only good luck prevented it."

Details of the New Idea

The following details of the new idea were provided by Benny
Peiser and Michael Paine and appear here with only minimal editing for
style and clarity:

The findings are calculated on the basis of the generally accepted
"impact rate" (i.e. the rate of cosmic impacts calculated from
terrestrial and lunar impact craters together with the currently
observable flux of asteroids and comets in the solar system). A
computer simulation of cosmic impacts over a 5 million-year period was
chosen to give an indication of the environmental disruptions that have
occurred during the evolution of our species.

These consequences can be categorized into:

A. Local -- devastation over a radius of tens of (miles) kilometers. No serious regional or global consequences

B. Moderate regional -- devastation over a radius of hundreds of
miles (kilometers) -- the size of a small country. Short-term regional
climatic problems.

For everything except the last category, the effects on early human
populations depend on proximity to the impact -- a matter of luck. In
addition to climate disruption (mainly darkness and cooling), the
larger impacts could lead to global warming due to the greenhouse
effect (water and carbon dioxide), loss of the ozone layer
(particularly with ocean impacts that propel chlorine into the upper
atmosphere), acid rain and toxins.

The simulation looked at the worst event in each of 5,000 millennia.
It therefore gives an underestimate of the total number of impacts.

The program recognizes five outcomes of an asteroid or comet colliding with Earth:

* The object skims the atmosphere and flies harmlessly back into space. This happened in 2 percent of the millennia.

* The object explodes above land in an airburst similar to an
atomic explosion. This happened in 17 percent of the millennia.

* The object impacts the land and forms a crater. This happened in 11 percent of the millennia.

* The object explodes in an airburst above an ocean. This was the
most frequent outcome, accounting for 41 percent of millennia.
Fortunately, until recently, most of these impacts would have been
harmless to land dwelling creatures.

* The object impacts the ocean, forming tsunami and, possibly,
ejecting vast quantities of water and salt into the atmosphere. This
happened in 28 percent of the millennia. (Larger impacts may also reach
the ocean floor and cause similar effects to a land impact)

Over the period of the simulation some 57 percent of millennia
suffered an impact that would potentially have consequences for
land-dwelling creatures. In most cases they would only be affected when
they were close to the impact site. The situation is different now with
significant human populations living in low-lying coastal areas.

Size impactor (The letters refer to the typical environmental consequences.)

1,650 to 2,950 feet (500 to 900 meters) (C): 108 events

0.6 to 0.9 miles (1 to 1.5 kilometers) (C/D): 24 events

1 mile (1.6 kilometers +) (D/E): 13 events

Craters (The letters refer to the typical environmental consequences.)

Over the 5,000 millennia a total of 552 craters were formed on land. Of these:

* 477 were less than 3 miles (5 kilometers) in diameter (A);

* 64 were between 3 and 6 miles (5 and 10 kilometers) in diameter (B);

* nine were between 6 and 12 miles (10 and 20 kilometers) in diameter (C);

* two were more than 12 miles (20 kilometers) (D).

There were also six ocean impacts that could be expected to produce
moderate-to-severe global climate disruption (D/E), particularly
destruction of the ozone layer. Three of these involved transient
craters more than 31 miles (50 kilometers) in diameter and would
probably have penetrated to the ocean floor.

Therefore, during this simulation severe climate disruption
occurred, on average, every million years (i.e., two land impacts and
three ocean impacts).

The findings by Peiser and Paine are underpinned by a significant
number of large impact craters. So far, 32 impact craters have been
discovered that are younger than 5 million years. One is 32 miles (52
kilometers) in diameter, three are between 6 and 12 miles (10 and 20
kilometers), one is between 3 and 6 miles (5 and 10 kilometers) and 25
are less than 3 miles (5 kilometers) in diameter. However, it should be
noted that it takes very unusual conditions to preserve craters of this
size for more than a few hundred thousand years.

Comment: One
thing is asteroids of which there are relatively little chance of
impact. Another thing which was highlighted by Victor Clube and has
been documented in a series of articles by Laura Knight-Jadczyk in the
last week or two, is the threat by cometary showers, which appear to be
cyclical and much much more frequent visitors to planet Earth than
asteroids. What also appears evident is that this information is being
severely repressed by the powers that be.

See the articles on "comets and catastrophe" using the links to the left of this article.

Astronomers have discovered the first near-Earth triple asteroid, which is hardly 7 million miles from our planet.

Known as 2001 SN263, the asteroid, with three bodies orbiting each
other, was discovered by astronomer Michael C. Nolan and his colleagues
using the sensitive radar telescope at Cornell University's Arecibo
Observatory in Puerto Rico.

The main, central body is spherical with a diameter of roughly 1.5
miles (2 kilometers), while the larger of the two moons is about half
that size. The smallest object is about 1,000 feet across, or about the
size of the Arecibo telescope.

Other triple asteroids exist in the asteroid belt (between Mars and
Jupiter) and beyond, but this is the first near-Earth system where the
actual shapes of objects can be clearly seen.

"This discovery has extremely important implications for ideas about
the origins of near-Earth asteroids and the processes responsible for
their physical properties," said Nolan.

"Double, or binary, asteroid systems are known to be fairly common -
about one in six near-Earth asteroids is a binary - but this is the
first near-Earth triple system to be discovered," he added.

The orbits of binary and now triple asteroid systems unveil the mass
and allow astronomers to assess whether they are stable over millennia
or have formed very recently.

According to Nolan, because of the small sizes and irregularly
shaped components, 2001 SN263 should offer unique insights relative to
the much larger triple systems in the main asteroid belt.

"Examining the orbits of the moons as we continue to observe 2001
SN263 over the next few weeks may allow us to determine the density of
the asteroid and type of material from which it is made," said Nolan.

"We will also be studying its shape, surface features and regolith (blanketing material) properties," he added.

Strange astronomical sights have been reported in the skies above Grantham this weekend.

Whether they were UFOs, space shuttles or just frenzied meteorical activity, no one is sure.

On Saturday night, at about 7.45pm, what looked like a spacecraft with a blazing orange trail was reported to have passed over the town.

The following night, between 9pm and 9.30pm, Shelley Jones was walking home when she spotted five large meteors fly across the sky.

She said: "We spotted the first one at 9pm.

"It came from the south heading north - each one on exactly the same
trajectory and at approximately four to five-minute intervals.

"Each became slightly larger and brighter than the first. The final
one was huge like a large ball of fire in the sky moving towards the
north."

Unfortunately, Shelley was unable to catch any of the activity in
the skies on camera, but she can't believe her and her husband were the
only ones to see it.

Comments:

A Journal website reader who did not want to be identified contacted
us to say she saw something similar a fortnight ago when she was
walking her dog in Sleaford.

She said: "I saw the same orange flying ball.

"I thought it was a comet or a shooting star at first and thought it was quite low and lasting a long time.

"It went over me and headed for the town centre from Grantham
direction. I carried on walking and about five minutes later it was
back over the top of me and stayed there for a while and then changed
direction and headed toward Lincoln direction.

"From underneath, it looked like it was on fire but the flames
looked as if they were some kind of liquid and there was no noise.

"I thought I was going mad and I wish I'd had my camera with me. I'm glad I'm not the only one to see this."

Multiple-witness sighting of large fireball and other unidentified
object(s) flying from West to East over the NJ shoreline. Object(s)
were reported to have allegedly crashed into the Altantic Ocean. Local
police and U.S. Coast Guard search missions were dispatched by boat,
helecopter, and on the beach.

Investigator Comments...

Oliver Kemenczky:

"The Normandy Beach sightings of September 1, 2007 were witnessed by
dozens of people at many different locations along the Eastern U.S.
seaboard, from as far North as Long Island, New York to possibly as far
South as South Carolina. Telephone calls were received by police, fire
department, and Coast Guard officials during the 8:30 PM to 11:30 PM
timeframe. The event, involving a fireball and other unidentified
aerial objects, was reported on radio and television newscasts, as well
as in new many newspapers and on the Internet. NY-SPI's primary
investigation focused on the actual location where objects were
reported to have "crashed" into the Altantic Ocean and in the area from
where the Coast Guard search had occurred. The Coast Guard search
encountered no debris on the surface of the water.

NY-SPI obtained the exact coordinates of the Coast Guard's search
missions (provided to us by the C.G.) and subsequently embarked on a
search of the ocean floor beneath the water. Our investigation team was
equipped with a diver, sonar, magnetometer, GPS, radar, an underwater
camera, and other search instrumentation. The team did not have high
expectations of actually finding or recovering what may have crashed
into the water, understanding that it was like looking for a needle in
a haystack. Assuming the search coordinates provided were correct and
assuming the object we were looking for had actually crashed in the
area that we had searched, there were still many possiblilties that
could have caused us to come up empty-handed. For example, the proposed
object may have embedded itself beneath the sand on impact; or clam
boats trawling the ocean floor may have buried it; or perhaps whatever
the object was (as witnessed on the water with the red beacon) may have
sunk and already been quietly recovered before we got there.
Nonetheless, we proceeded with our search and the case remains and open
mystery. Additional witnesses have come forward to NY-SPI with their
accounts since the investigation was filmed."

Ted Davis:

"Beach closings, beached mutilated fish, an unidentified aircraft
crashing into the ocean, an exploding fireball, a Coast Guard rescue
mobilization and a stir of media reports. This sounds more like a case
from the X-Files than a real life UFO sighting that shook the
picturesque beach communities along the New Jersey shore right before
Labor Day in the late summer of 2007.

The initial media buzz surrounding this case was quite substantial,
drawing our attention only a day or two after it first occurred.
Numerous stories in print and on the internet cited the local
authorities and Coast Guard as receiving high volumes of calls on the
night of the incident. However, when NY-SPI contacted the local
authorities to identify additional witnesses we learned that most of
the calls connected to the incident were in fact from members of the
media, not eyewitnesses.

All the witnesses interviewed by the NY-SPI team were extremely
credible, each one having spent many summers at the Jersey Shore. Every
witness maintained a consistent story, describing what they saw, never
attempting to jump to conclusions beyond the facts of the case. Most
intriguing of all was the claim by the three teenagers (Anthony, Gregg,
& Dallas) that they clearly overheard Coast Guard/police radio
chatter on the beach that night reporting that wreckage HAD been
recovered during the Coast Guard search. This is in direct conflict
with the Coast Guard report that no evidence of a downed aircraft had
been recovered during their search. Unfortunately, with no other
sources to corroborate the teenagers' report, NY-SPI is unable to
arrive at a definitive conclusion that wreckage (from some sort of
crash) was located in the waters off Normandy Beach that night.

While some eyewitnesses (like Matt Sosnowski) described an object
virtually identical to a fireball (sporadic meteor), we were unable to
locate a single eyewitness reporting an exploding fireball, as was
indicated in a variety of media sources.

Initially we were extremely interested in rumors of beaches closings
in the days following the incident. NY-SPI obtained both print and
television news report verification that beaches in the area of
Normandy Beach were in fact closed in the days following the incident
due to medical waste from an unknown source washing up on shore. While
this seemed like an uncanny coincidence, we were never able to connect
these unexpected closings (the beaches in this area have been
relativley clean for a number of years). Outside of a conspiracy theory
there is nothing definitive to tie the beach closing to this case. One
possible explanation considered by the team was that a meteorite
impacting the ocean floor had dislodged medical waste that had been
deposited many years ago. As with much of this case, there is no
evidence to support this theory.

NY-SPI team members spent an entire day searching the waters off the
Jersey shore within the coordinates provided by the Coast Guard. While
the search did not yield any evidence (either of a meteorite or
aircraft wreckage), we knew it was a long shot with such a large area
to search and the event having occurred several months earlier. But
since the Coast Guard had only conducted a surface search, we had to
take a chance.

In the end, the NY-SPI team felt we were dealing with several
independent events. 1. One or more fireball meteors, which may or may
not have exploded over the Jersey shore. 2. Some sort of aircraft
(likely military related) crashing into the water off Normandy Beach.
Again, there is limited evidence to support these findings so these are
preliminary theories at best. We reserve the right to change our
theories if and when new evidence emerges, as would any good scientist
or investigator.

Most significant of all was the media influence on the development
of this case. Here we have an excellent example of media distortion
feeding upon itself and blowing a case into something much grander than
it ever was in actuality. That being said, it was a fun case to
investigate. I just wish we could have mobilized while it was still
warm; the beaches were beautiful and inviting despite the frigid
weather."

Dennis Anderson:

"I was not available to interview witnesses, therefore, my
observations are strictly astronomical in nature. All descriptions of
the event in my opinion, point to a fireball. The flight trajectory,
the colors and appearance are consistent with a meteor of this type.
The Aurigid meteor shower peaked that morning, and was most visible
from the west coast. Meteors can usually be seen a day or two before
and after a shower's peak. However, the direction of flight if reported
correctly, would indicate the object seen was not related to the
shower. I believe it was a sporadic meteor, which had no association
with the shower. There is the possibility of an overlapping event
having taken place that night, but I will leave that to other members
of the NY-SPI team that investigated that part of the case."

Denise Petty:

"The Normandy Beach case is a perfect example of how, at first, many
seemingly different testimonies, once pieced together, correlate to a
cohesive event. When an event occurs, it is very rare that each witness
views the event from exactly the same point of view. These differing
points of view need to be analyzed to determine where each piece of the
puzzle fits into the larger picture.

Case in point: Dallas and the other teenagers on the beach in
Normandy Beach report a very different event than that which was viewed
by Gail Steinbacker in Ortley Beach. What gave Dallas' testimony the
heaviest weight was the corroboration by her father. This helped
eliminate the attention-seeker equation seen many times when recall of
events are presented. Her testimony did not change.

Further supporting this is USCG Petty Officer Sova's relation of the
events. While I believe he was being honest based on my experience, I
also have intimate knowledge of military training exercises used during
basic training that allows a service-member to relate events and not
give any body language or eye-movement cues. I believe that he related
the facts as they were related to him. Yet I do not rule out the
possibility that there is more information held by the military that
was not divulged to the NY-SPI team. Repeated FOIA requests may yet
yield additional information over time.

With all of the above taken into consideration, together with the
various media reports, I believe that there was an event of consequence
that occurred on that beach that night. I believe that no one knows
exactly what happened, and I also believe that this investigation is
not yet resolved."

If you spotted bright lights streaking across the predawn sky this morning, you weren't alone.

And no, it wasn't a UFO. Turns out it was a meteor blazing across
the sky about 5:30 a.m. Calls started pouring into the Federal Aviation
Administration immediately, said a representative at the agency's
Renton, Wash., operations center. He said air traffic control center
operators confirmed it was a meteor.

The FAA representative said the agency got calls from early risers
in Oregon, Washington and Idaho who wondered what it was they'd seen.

Got pictures or video of the meteor? Send it along to newsroom@news.oregonian.com.

AN EXCEPTIONALLY LARGE METEORoid storm was
detected on the moon by the Apollo seismic network between 20 to 30
June 1975, attaining daily impact rates five to ten times larger than
the normal steady rates [1]. The storm has been interpreted as arising
from a meteoroid cloud with a diameter of 0.1 astronomical unit and a
total mass of [10.sup.13] to [10.sup.14.g.] Duennebier et al. [1] have
estimated that a total mass of fragments of about 1.8 X [10.sup.6] g
collided with the moon during the event.

To the best of our knowledge, however, no effects on Earth were reported as arising from this large event. Given the cross sections represented by Earth in comparison to the moon, a total meteoroid mass of about 2.4 X [10.sup.7] g should have impacted Earth during the 10-day period,
which corresponds to an average of 2.4 x [10.sup.6] g/day. This is one
order of magnitude larger than the most important regular Geminid
meteoroid shower of about 1 X [10.sup.5] to 3 X [10.sup.5] g/day (0.1
to 0.3 ton/day) [2, 3]. These numbers, however, are likely to be larger
for Earth because of its larger accretion effect [4].

The June 1975 storm was thought to be a very rare event because of
its exceptional strength [1, 5]. The radiant direction was toward the
sun. There is a suggestion that it could be an enhancement of the well-known [beta]-Taurid daytime shower [5]. Brecher [6] suggested that the June 1975 meteoroid storm was associated with the "Canterbury Swarm" as a result of the remains of an early Comet Encke fragmentation,
which would also include the [alpha]-Taurid and [beta]-Taurid showers
and two asteroids (2212 Hephestos and 1982 TA). According to Brecher
[6], the close encounter of such fragments with the Earth-moon system might
have produced some extraordinary events in the past, such as the 25
June 1178 flash on the moon, reported by a Canterbury monk, and the 30
June 1908 Tunguska event in Siberia.

The storm might also be the result of a more recent large fragmentation event in space.
Such an event was suggested by Halliday [7], in order to explain the
first observational detection of multiple meteorite falls from the same
orbit (the Innisfree and Ridgedale meteorites, detected on 6 February
1977 and on 6 February 1980, respectively, almost at the same universal
time (UT) and falling less than 500 km from each other).

We decided to inspect old data on very low frequency (VLF)
propagation obtained in the period. Long-distance VLF transmissions
propagate in an Earth-ionosphere spherical waveguide, according to
well-known models [8, 9]. The VLF phase variations are directly related
to changes in the height of the upper boundary of the waveguide,
located in the low terrestrial ionosphere. The boundaries are set by a
certain electron density. Nighttime height is typically 85 km at the
ionosphere E region, whereas daytime height is 70 km at the D region.
On the other hand, meteoroids are known to produce ionized
trails as the result of conversion of the kinetic energy of the meteors
into potential energy of ionization as the meteors are slowed
down by collisions with gases in the upper atmosphere [10].
Observational results and model predictions, assuming a dustball
structure for meteoroids, relate their masses to the heights where the
trails are defined [11, 12]. For trails ending at 85 and 70 km, the
meteoroid masses should be in the range of 0.1 to hundreds of grams,
respectively (these figures should be considered as lower limits).
Indeed, for the June 1975 storm, Duennebier et al. [1] estimated the
density of the cloud, for an assumed distribution for the detected
objects, and found that 18% of the mass in the observed range (50 g to
50 kg) was in the fraction with mass greater than 5 kg.

The effects of regular meteoroid showers in VLF transmissions have
been known for some time [12, 15]. However, the showers are known to
produce small 4 to 7 [delta] deviations in nighttime mean phase levels,
which can be observed only in the absence of other anomalous
propagation effects (caused by particle precipitation and high
geomagnetic activity).

We searched for effects of the June 1975 event on the VLF
propagation paths shown in Fig. 1. Data were available in strip charts
and were reduced every 30 min. The transmissions received at Itapetinga
Radio Observatory, Atibaia, Brazil, were from the radio transmitters
Omega-Trinidad (at 10.2 and 13.6 kHz), Omega-Haiku, Oahu, Hawaii (10.2
kHz), and NAA, Cutler, Maine (17.8 kHz). Omega-Japan (10.2 and 13.6
kHz) transmissions were received at the University of Queensland,
Brisbane, Australia. Propagation data from NLK (18.6 kHz), Jim Creek,
Seattle, Washington, obtained at Nishinomiya, Japan, did not show any
important anomaly in the period of interest [16]. NAA (17.8 kHz)
signals received at Thule, Greenland, Exhibited a smooth change in
diurnal phase variation, with a minimum signal late in June [17], a
normal effect that may be attributed to a seasonal dependence, because
that propagation path is under sunlight nearly all the time in the
northern summer.

Limited by the observing schedules, the data gathered at Atibaia
covered the period 17 to 30 June 1975, and the undisturbed days used
for comparison were 17 and 18 June 1975. The data from Brisbane covered
a larger period, 3 June to 15 July 1975, with the best undisturbed days
28 June to 13 July. The NAA data received at Atibaia were difficult to
analyze and required daily adjustments, because of the phase jumps that
occur when the two transmitting antennas are switched. Omega-Japan
(13.6 kHz) and other VLF data received at Brisbane were quite noisy and
difficult to analyze.

The VLF propagation anomalies, correlated in time with the June 1975
meteoroid storm, have been detected in four ways: (i) a daytime phase
advance in the period; (ii) large anomalous nighttime phase advances
(lasting a few hours on some days) particularly pronounced on
Omega-Trinidad transmissions, where they attained amplitudes comparable
to Lyman-[alpha] ionization during sunrise; (iii) a phase advance of
the mean nighttime phase level and a reduction in the diurnal phase
variation, which were partly caused by the important anomalies (ii);
and (iv) a pronounced reduction in sunset phase delay time rates, at
all transmissions, indicating the presence of an extra ionizing source.
In 21 years of VLF observations in Brazil, we had not seen effects (i),
(ii), and (iv) before.

The VLF phase behavior in the period of interest, for the shortest
southern propagation path (Omega-Trinidad to Atibaia, Brazil), is shown
in Fig. 2. We filtered the data, subtracted the normal diurnal phase
variation, and used the mean readings from 17 and 18 June 1975 as
typical. The most important anomalies are evident, such as the steady
daytime phase advance of about 2.9 degrees/Mm (at 10.2 kHz; units are
in degrees per megameter of propagation path) and 1.8 degrees/Mm (at
13.6 kHz) from 19 to 28 June 1975; the steady nighttime phase advance
and large anomalies, which consequently contributed to the reduction in
the mean diurnal phase variation.

These effects were also present in the other transmission, but to a
lesser extent relative to the larger normal diurnal phase variations
(because of the longer paths). The effects are more pronounced at the
lower VLF frequency of 10.2 kHz (Fig. 2), a trend confirmed in all
other transmissions analyzed in this study.

The large nighttime phase advances are particularly pronounced on 23
and 26 June 1975. They might be attributed to ionospheric disturbances
produced in the daytime side of Earth, affecting the nighttime
ionosphere as well through a number of mechanisms, such as traveling
disturbances guided by E-region winds [10].

On the other hand, in Fig. 3 we show the daily deviations of the
diurnal phase variations with respect to the mean in undisturbed days
for all transmissions (in degrees per megameter of path length),
compared to the meteoroid impact rates on the moon [1]. The correlation
is rather remarkable, especially in the period 22 to 29 June 1975. The
Brisbane data, however, suggest that the effects started several days
earlier, becoming further enhanced on 20 to 26 June, disappearing
afterwards. Similar plots are obtained for the other anomalies.

During the storm period, the sunset phase delay slowed with time
became considerably smaller than the normal one in most of the
transmissions. However, no anomaly was found in the sunrise phase
advance slope with time. The sunset phase delay is the result of a
combined effect of electron-ion recombination and the terminator
movement along the propagation path. The phase delay time rate
([[phi].sub.D]) may be represented as approximately [[phi].sub.D] =
[[phi].sub.N] - [[phi].sub.Nq] where [[phi].sub.N] is the normal rate
of change of phase at sunset, which is the observed disturbed rate, and
[[phi].sub.q] the change due to the production rate, q, of electrons
attributed to the meteoroids. An order of magnitude of the rate of this
production may be estimated assuming that in general any phase change
is related to the well-known continuity equation ([phi] [alpha] (dn/dt)
= q - [[alpha n.sup.2], where n is the electron density and [alpha] is
the recombination coefficient). After some algebraic manipulations we
obtained: [Mathematical Expression Omitted]

We plotted the difference between the mean value for undisturbed
days (<[[phi].sub.N]>) and [[phi].sub.D] for each disturbed day
(Fig. 4). These are given in units of degrees per megameter per hour.
the typical <[[phi].sub.N]> was 5 (Omega-Haiku, 10.2 kHz), 8.3
(Omega-Trinidad, 10.2 kHz), 9.8 (Omega-Trinidad, 13.6 kHz), and 14
(NAA, 17.8 kHz) for the transmissions received in Brazil, and 4.6
(Omega-Japan, 10.2 kHz) for transmission received in Australia. We
assumed that both [alpha] and n remained close to their typical values
at an intermdiate daytime and nighttime low-ionosphere height [18],
that is n [nearly equals] 6 X [10.sub.2] [cm.sup.-3], [alpha] = 4 X
[10.sup.-6] [cm.sup.3] [s.sup.-1] at about 80 km. We then obtained an
estimate of the electron production rate attributable to the meteoroid
storm q [nearly equals] 0.3 to 0.9 [cm.sup.-3] [s.sup.-1] on the most
disturbed days, which is three to nine times larger than estimates
given for the large 1946 Giacobinid shower [2].

The unusual effect of daytime phase advance (Fig. 2)
suggests that the long-lasting ionizing effects of the storm were so
strong that they were able to modify significantly the daytime upper
boundary of the Earth-ionosphere waveguide (that is the D
region). We may also estimate the ion production rate to account for
the daytime phase advance, using again the continuity equation and the
Earth-ionosphere waveguide theory [8, 9]. Taking the daytime phase
advances at the Omega-Trinidad transmissions received at Atibaia (Fig.
2), we infer a reflection height reduction of 1.5 km. Using a
relationship for height reduction versus ion production rates, derived
for solar flare x-ray effects [19], we estimate q [nearly equals] 3
[cm.sup.-3] [s.sup.-1] attributable to the storm, at an altitude of
about 70 km.

Comparing the different VLF transmissions, the effects are
considerably larger on the Trinidad-Atibaia path, which extends mostly
in the Southern Hemisphere. This might indicate a directional property
for the impacting stream of meteoroids. If we assume that the meteoroid
storm effects were predominantly a Southern Hemisphere phenomena, we
can tentatively reduce the anomalies for the corresponding southern
sections of path lengths. The Omega-Trinidad, Omega-Haiku, and NAA
paths to Atibaia are 60%, 50%, and 33% in the Southern Hemisphere,
respectively. Omega-Japan to Brisbane path is 40% in the Southern
Hemisphere. If we normalize the effects for the corresponding fractions
of the paths, the magnitude of the effects (such as those shown in
Figs. 3 and 4) are no longer so discrepant for the different
transmissions. Similar results are found to the other two effects. It
is also meaningful that the VLF propagation paths located entirely in
high northern latitudes [Jim Creek to Nishinomiya and NAA to Thule
(Fig. 1)] [16, 17] did not exhibit any anomaly in the period, except
for smooth seasonal variations.

On the other hand, it was found that the meteoroid ionization
effects remained during sunset hours, although they were not present at
the sunrise phase advance period. The sunset effect was measured at the
linear part of the phase delay with time, as the terminator moved from
the receiver to the transmitter sites (Fig. 1). Depending on the
transmission, the effect remained up to 1.5 to 3 hours after sunset at
the receiver site. Therefore we suggest that the radiant right
ascension was larger than the solar right ascension by about 1 to 2
hours. Since the sun's right ascension was about [90degrees], the
suggested storm radiant was 105[degrees] to 120[degrees]. None of the
well-known meteor showers are located in the Southern Hemisphere, at
such right ascension [20], except, perhaps, the Corvids shower, which
was observed only in 1937 (dec. = -10[degrees], right ascension =
191[degrees]). It is likely that the June 1975 event was caused by a
genuine sporadic meteoroid storm.

Finally, the peak impact per day rate on the moon, detected
on 23 June 1975, does correspond to a larger ionization effect on
Earth's upper atmosphere (Figs. 2 and 3). However, the
largest ionization effect on 26 June 1975, does not show a clear
correspondence with impacts on the moon. Interpretations should be made
carefully, since the effects on Earth's ionosphere are believed to be
complex and largely smoothed out in time, compared to the direct
detection of impacts on the moon. However, the lack of strict day to
day correlations between data from Earth and moon suggest that the
meteoroid stream was not homogeneous in space.

[21] CRAAE is supported by the Universities of Sao Paulo, Mackenzie,
Campinas, and the Institute of Space Research. This research was
partially supported by Financiadora de Estudos e Projectos. One of the
authors (V.L.R.K.) had a Coordenaqao de Aperfeicoamento de Pessoal de
Nivel Superior fellowship.

Astronomers have long stated that a large number of meteoroids
frequently impact the Earth. Such incidents are rarely reported despite
the enormous amount of energy released. However, newly-declassified
documents show that secret military surveillance systems have been
detecting such events.

Military satellites have been watching huge meteoroids slam into Earth's atmosphere for nearly two decades.

IN A CELEBRATED 1983 paper, Caltech planetary astronomer Eugene
M. Shoemaker calculated that every year, on average, a fragment of
asteroid or comet self-destructs somewhere in Earth's atmospherewith the kinetic-energy equivalent of 20,000 tons of TNT, or about
|10.sup.24~ ergs. (The devastating Tunguska event in 1908, by
comparison, delivered the equivalent of about 10 million tons of TNT.)
Such large meteoroids would presumably be some 10 meters across, weigh
upward of a thousand tons, and arrive at between 15 and 20 kilometers
per second.

Fortunately, nonmetallic objects of this size are annihilated at
altitudes too high to harm anything on the ground (S&T: March 1993,
page 15). Still, no matter how high, a 20-kiloton explosion is not easily overlooked. It would, for example, eclipse the yield of the fission bomb that destroyed Hiroshima in 1945. Furthermore, in recent years the
36-inch Spacewatch telescope in Arizona has discovered numerous
house-size objects hurtling through space very near the Earth.
Based on these close calls, former Spacewatch team member David L.
Rabinowitz (Carnegie Institution of Washington) concludes that Shoemaker's estimates of encounter rates were too conservative by 10 to 100 times.
In the Astrophysical Journal for April 10, 1993, Rabinowitz counters
that Earth should endure a 20-kiloton blast roughly every month and
receive hundreds of kiloton-yield jolts annually.

Surprisingly, these cosmic cannonades are rarely reported-- only a handful are known from the last few decades. One was a
dazzling, nighttime fireball over south-central British Columbia in
March 1965, another a widely observed, daytime bolide that grazed
Earth's atmosphere over the Rocky Mountains in August 1972. The sparse sightings hardly jibe with predictions of weekly events. So what's going on?

Much of the answer lies in an unprecedented body of spaceborne
observations declassified and released in October by the U.S.
Department of Defense. The report details a 17-year record of sightings made from orbit by satellites under the control of the U.S. Air Force Space Command. It will appear as a chapter in the book Hazards Due to Comets and Asteroids, to be published next year by the University of Arizona Press.

According to Edward Tagliaferri (ET Space Systems), the report's principal author, infrared scanners on military
satellites have recorded a total of 136 atmospheric explosions since
1975, an average of eight probable meteoroids per year, each with an
energy of roughly 1 kiloton or more. That's just the kind of
observational input cosmic oddsmakers were hoping for. "I've been aware
of this data for a long time," says Shoemaker, "and I've been waiting
for the time when this could be released." Much of the credit for
getting the once-secret database declassified goes to Simon P. Worden,
a former astronomer who until recently headed a division of the
Ballistic Missile Defense Organization (the "Star Wars" group).

Although the report neither discloses the identity of the
surveillance system nor reveals details about its sensors, other
sources suggest that the data have come from early-warning satellites
of the Defense Support Program. Operating at the geosynchronous
altitude of 38,000 km, the DSP sentinels use sophisticated detectors to monitor the Earth's upper atmosphere for rocket plumes and nuclear explosions.
One type of sensor "stares" continuously at the entire disk. The
high-altitude flashes it looks for are both brief and bright, making
them detectable even in daylight against the slowly varying background
of Earth lower down. If the airburst is vivid enough, a companion,
visible-wavelength device then pinpoints its location.

Another sensor system uses arrays of supercooled detectors tuned to
2.78 microns, an infrared wavelength absorbed virtually completely by
water vapor in the lower atmosphere. Married to large Schmidt optics
with a 3.6-meter focal length, the array sweeps over Earth's
infrared-dark disk every 10 seconds with enough sensitivity and spatial
detail to pick up the hot exhaust of even modest ballistic missiles.

The new accounting is still well shy of the hundreds of comparably powerful annual events predicted by Rabinowitz.For example, the brightest flash recorded from orbit since 1965
probably resulted from a kinetic-energy yield of roughly 5 kilotons. One
reason for the shortfall is that many airbursts go unreported, even
though satellites detect them, because the systems and their handlers
are watching for hostile activity and often either overlook or ignore
natural events. Furthermore, the meteoric flashes last only a second or two, so on average the scanning infrared arrays miss at least four events for every one they glimpse. Allowing for such gaps, Tagliaferri estimates that at least 80 kiloton-yield meteoroids probably strike the Earth every year,
a bombardment frequency higher than that derived by Shoemaker but still
below the rate extrapolated from the Spacewatch discoveries.

Notably, of the 136 infrared events, only three turned up in records
from the visible-light burst detectors, which have been flown since the
early 1980s. Coincidentally, all three caught the attention of two
satellites simultaneously. One occurred some 30 km above the
western Pacific Ocean on October 1, 1990 -- a 2-kiloton blast right in
the midst of the Kuwait-Iraq conflict. An observer on the ground below
would have seen part of the sky briefly blaze like the Sun and would
have heard a loud, low rumble soon thereafter. "Had this
occurred over Kuwait it could have been a sticky situation," Worden
observes. "We could tell it was natural, but they could not." Impact
specialists hope the release of the previously classified records
represents the first step in a long-term partnership with the
surveillance community. They are pushing to have spacecraft collect
such pivotal data more reliably and have it distributed openly. But
Tagliaferri acknowledges that the existing systems have national-security objectives that simply cannot be compromised.
One possibility, currently under negotiation, is to include comparable
detectors on civilian satellites like those in the Global Positioning
System.

Meteor researcher Douglas O. ReVelle (Los Alamos National
Laboratory) notes that this is not the first time a defense-related
system has yielded clues about the extraterrestrial infall rate. A
global network of sensors operating between 1960 and 1974 (some from
the rooftops of selected U.S. embassies) detected low-frequency
acoustic waves from a handful of powerful airbursts that were probably
meteoric in nature. One was believed to result from a small asteroid perhaps 20 meters across that fell harmlessly between South Africa and Antarctica on August 3, 1963 -- even though it packed the explosive punch of a half million tons of TNT!

With so many cosmic bombs bursting overhead one still has to wonder
why there are so few visual reports of very bright bolides. Peter
Brown, director of the International Meteor Organization for North
America, offers at least two possible explanations. First, it may be
that much more of the fireballs' energy is released in the infrared
(where they're being detected) than at visible wavelengths (where
they're not). Also, only in the last few years have fireball reports been collected on a systematic basis.
In the future, he adds, the IMO and other meteor networks will be
working more closely with their military counterparts to create a more
complete record.

Meteorites provide information about the formation of the Solar
System. They are pieces of very old material that have fallen from
space to the Earth. Most result from asteroid collisions in the
Asteroid Belt between Mars and Jupiter, but over a dozen from the Moon
and another 12 from Mars have also been identified. The three main
types of meteorite are stone, iron, and stony-iron. Stony-iron
meteorites are the rarest and are often quite beautiful. Antarctica is
the best place to find meteorites because there the ice and aridity
preserve them, sometimes for as long as a million years.

Each year approximately 40,000 tonnes of extraterrestrial material,
most of it dust, bombards the earth. But where does it come from, and
why does it land here?

Visitors from space arrive on the Earth with amazing frequency, not
as alien monsters or little green people in flying saucers, but as
meteorites, extraterrestrial material ranging from the tiniest of dust
grains to enormous impact crater-forming bodies. Meteorites were formed
at the birth of the Solar System, about 4,560 million years ago. We
have no material on Earth this old, so it is only by studying
meteorites that we can learn about the processes that shaped our Solar
System and our planet.

Our Sun was born in a rotating cloud of gas and dust, called a
nebula. Gradually this cloud collapsed and dust grained joined together
to form bigger and bigger bodies, eventually producing the Sun and
planets. The Sun is at the centre of the Solar System, and all the
planets orbit around it.

The Asteroid Belt, the place from which most meteorites come, lies
between Mars and Jupiter. Asteroids orbit the Sun at a distance three
times that of the Earth from the Sun -- three Astronomical Units (AU),
or 450 million kilometers. There are several thousand asteroids, the
largest of which is about 1,000 kilometers across (the Earth has a
diameter of about 13,000 kilometers). These rocky, metallic or
carbon-rich bodies are the remaining after the planets formed;
Jupiter's gravitational pull prevented them from joining together to
form a single planet.

The asteroids are in stable orbits around the Sun, but occasionally,
thanks to the influence of Jupiter, the orbit of an asteroid is altered
so it collides with another and breaks up. Fragments of broken asteroid
fall to Earth as meteorites.

We know that meteorites came from the Asteroid Belt as fireballs
created by incoming meteoroids because they have been photographed.
From their direction and speed, scientists can calculate the orbits of
these meteoroids, and all are seen to extend out to the Asteroid Belt.

One of the most recent meteorite falls occurred on a Friday afternoon in October 1992. at Peekskill, New York.

S. Eichmiller's extraordinary photo of the Peekskill fireball of October 9, 1992

The track of the fireball was recorded on several video cameras,
mostly by members of the public attending outdoor football games. The
video footage has been edited together to produce a film of the
fireball travelling over the northeastern U.S.

The Peekskill meteor of 1992 was captured on 16 independent videos and then struck a car.

As well as meteorites from the Asteroid Belt, Earth has also
received more than a dozen meteorites that have come from the surface
of the Moon. Lunar meteorites have been compared directly with samples
brought by the Apollo and Luna missions. The surface of the Moon is
covered in the craters caused by impacting bodies. The force of these
impacts is sometimes sufficient to throw material off its surface, and
it is this that arrives on Earth. In the same way, rocks have come to
us from Mars: scientist have identified 12 Martian meteorites.

The very bright fireball often associated with an incoming meteoroid
is the result of frictional heating as the body travels through the
atmosphere. Only the outermost surface melts; the resulting droplets of
molten material are carried away by the speed of passage. Finally, as
the molten surface rapidly cools to a glassy coating, or fusion crust,
which helps scientist identify meteorites. The interior of a meteorite
remains cool and unchanged, and meteorites are cold when they land.

The
Peekskill Meteorite is composed of dense rock and has the size and mass
of an extremely heavy bowling ball. If you are lucky enough to find a
meteorite just after impact, do not pick it up -- parts of it are
likely to be either very hot or very cold.

The very smallest of micrometeorites do not melt as they pass
through the atmosphere, whereas those that are slightly larger melt and
form tiny rounded droplets. Very large meteorites fall only every
million years or so. Arizona's 1.2 kilometre-diameter, Meteor Crater,
was produced by the impact of an iron meteorite about 50,000 years ago.
The original meteorite weighted up to 25,000 tonnes, and would have
been about 35 to 40 metres across, but most of it was vaporised by the
impact. A really big meteorite, probably about 10 kilometres in
diameter, fell at Chicxulub on the Gulf of Mexico about 65 million
years ago. As well as forming a crater 200 to 300 kilometres across,
the environment changes brought about the impact are thought by many
scientist to have resulted in the extinction of the dinosaurs. Several
smaller meteorites weighted about a kilogram fall on the Earth every
year, but only five or six are seen to fall. The last one seen to fall
in England was in May 1991, at Glatton, near Peterborough. This stony
meteorite weights just over half a kilogram and fell through a hedge of
conifers in the garden of a Mr Pettifor, who was started by the whining
noise it made as it hurtled through the air.

Meteorites are pieces of ancient material that survive their fall to
Earth from space. There are three main types of meteorite (stone, iron
and stony-iron), reflecting their main composition. Meteorites are
named after a place near where they fall or are found. Most meteorites
(96 per cent of falls) are stony, made up of the same minerals as many
terrestrial rocks, minerals containing silicon, oxygen, magnesium, iron
and calcium. Stony meteorites can be sub-divided into those which have
formed from melts of their parent bodies (like terrestrial igneous
rocks), and those which have remained unchanged since formation, or
aggregation. The latter are known as chondrites, after the small
rounded droplets of once-molten material (chondrules) they contain.

Iron meteorites comprise, as their name implies, mainly iron metal,
and generally contain between seven to 15 per cent of their weight in
nickel. These meteorites have been formed during the melting of the
parent bodies from which the meteorites originated.

The final main sub-division of meteorites is the stony-irons: a mix,
as the name suggests, of stone and metal. These are very rare
meteorites and beautiful in appearance. They are produced from the
intergrowth of iron and magnesium silicate minerals with iron metal.
Like iron meteorites, they were formed during the melting of their
parents.

Different types of meteorites provide evidence about events that
have occurred as the Solar System formed and evolved. Iron meteorites
are the closest physical analogy we have to the material that forms the
Earth's core. The stony meteorites represent material from the
core/mantle boundary of their parent body.

The most primitive meteorites, the CI carbonaceous chondrites, are
rich in water, sulphur and organic compounds. These might be the
material remaining from comets, which are essentially a mixture of ice
and dust, after all the ice has evaporated. It is material like this
that brought volatiles to the newly-formed Earth, and helped
established its atmosphere and oceans.

Several of the 12 Martian meteorites found on Earth contain pockets
of glass formed during the shock event that ejected them from the
surface of Mars. When this glass is melted in the laboratory, gas that
was trapped inside the glass by the shock is released and compared with
that analysed by the Viking space probes in 1976. The compositions are
similar, although Martian meteorites also contain carbonate grains,
produced below the surface of Mars when water circulated through the
planet. A recent report by scientists from NASA has described evidence
for fossilised martian bacteria inside these carbonate patches, showing
that life might once have existed there. By studying meteorites like
this, we can learn about events that have taken place in the past on
our neighbouring planet, a planet whose surface now appears to be dry.

Secret data from military satellites in orbit thousands of miles
above Earth show that the planet is continually bombarded by big
meteoroids that explode in blasts the size of atomic detonations. The
data, from spacecraft meant to watch for rocket firings and nuclear
explosions, were declassified recently by the Defense Department and
are to appear later this year in a book.

From 1975 to 1992, the satellites detected 136 explosions high in
the atmosphere, an average of eight a year. The blasts are calculated
to have intensities roughly equal to 500 to 15,000 tons of high
explosive, or the power of small atomic bombs. Experts who have
analyzed the data are publishing it in the book, Hazards Due to Comets and Asteroids, say
that the detection rate is probably low and that the actual bombardment
rate might be 10 times higher, with 80 or so blasts occurring each year.

The disclosure of a new class of large meteoric impacts is seen as
bolstering the idea that Earth is subjected to strikes from space in a
wide range of severities, including an occasional doomsday rock perhaps
once every 10 million years or so that causes mayhem and death on a
planetary scale.

The new data are also being praised as a cold-war spinoff
that can aid the cause of world peace by preventing false warnings of
nuclear attack. Indeed, it turns out that Federal analysts on several
occasions have struggled quietly for months to determine if such
explosions were natural or manmade.

Finally, impact specialists hope the release of formerly secret data
will be repeated and promote a new alliance between astronomers and the
keepers of military reconnaissance.

"It's important," Dr. Eugene M. Shoemaker, an astronomer at the
Lowell Observatory in Flagstaff, Ariz., who helped found the field of
Earth-impact studies, said of the new data in an interview. "It's a
unique source of scientific information."

Sky and Telescope magazine, based in Cambridge, Mass.,
which discusses the data in its February issue, lauded the once-secret
sightings as "an unprecedented body of spaceborne observations."

Sighted for ages but understood in detail only recently, meteoroids
are rubble left over from the creation of the solar system. They are
composed of ice, rock, iron and nickel in a variety of shapes and sizes.

Meteor showers and individual streaks of light that flash across the
sky every night are generated when tiny flecks of celestial detritus,
often no larger than grains of sand or pebbles, burn up while speeding
through the atmosphere.

In contrast, the blasts seen by the military satellites are produced
when speeding objects up to the size of large houses are heated to
incandescence and then explode about 17 to 20 miles above Earth. They
create vast fireballs and powerful shock waves that nonetheless leave
few or no discernible traces on the ground, since they begin so high
up. If made of dense metal, meteoroids of this size have a good chance
of punching through the atmosphere to hit the ground.

Scientists have suggested that once every 10 million years or so a
truly colossal object from space cuts through the atmosphere and slams
into Earth, sending up a global pall of dust that blots out the Sun,
alters the climate and changes the course of evolution by killing off
many plant and animal species. Such a menacing rock is thought to have
carved out a 185-mile-wide crater 65 million years ago that now lies
buried in the Yucatan Peninsula of Mexico. Its cataclysmic impact is
believed by some scientists to have caused or assisted in the
extinction of dinosaurs.

In general, the new observations are of a class of meteoroids too
big to burn up harmlessly in the sky as shooting stars but too small to
slice through Earth's atmosphere and strike the ground. They are middle
children in the meteoroid family.

Previous Lack of Reporting

By definition, meteoroids are small bodies speeding through space
that strike Earth's atmosphere. They can be comets made of ice or
asteroids made of stone or metal. Meteors are streaks of light seen
when meteoroids are heated while traveling through the atmosphere.
Meteorites are the parts of relatively large meteoroids that survive
passage through the atmosphere and fall to Earth as chunks of metal and
stone.

The scientists who are publishing the new observations say the
explosions of large meteoroids previously went largely unreported for
many reasons. The vast majority occurred over the oceans or desolate
parts of the continents. Many were obscured by clouds. And even when
occurring in broad daylight and rivaling the Sun in brightness, the
explosions lasted only a second or so, limiting the opportunities for
observation.

"There's many more of these objects impacting the Earth than we
previously thought," said Dr. Edward Tagliaferri, a physicist who was
the lead author of the satellite report. "Their discovery is a
fascinating story." Dr. Tagliaferri is a consultant for the Aerospace
Corporation, a nonprofit engineering firm in El Segundo, Calif., that
helps the Air Force run its numerous satellites.

The data were declassified by the Government last fall and are to be
published this July or August as a chapter in the new book on meteoroid
hazards, which is being published by the University of Arizona Press.
The book grew out of four symposiums on meteoroid hazards and is being
edited by Dr. Tom Gehrels, a planetary astronomer at the university who
organized one of the meetings.

Dr. Gehrels heads a small team of astronomers who use a 36-inch
telescope on Kitt Peak, west of Tucson, to search the sky for asteroids
in orbit around the Sun that occasionally intersect Earth's orbit and
one day might strike the planet. The effort is known as Spacewatch.
Such research has so far identified a total of 185 potential
interlopers. Generally these are larger than the objects that set off
the satellite-observed explosions. Yet the mere existence of the big
ones, and other clues like the heavy cratering on the Moon, have long
implied that space is filled with swarms of smaller objects, which went
largely unreported until now.

Findings Are Consistent

"It's a very interesting situation," Dr. Gehrels said in an
interview. "Spacewatch is finding a certain number of objects in space
that agrees with the things Tagliaferri is finding. The picture is
consistent."

From such data, scientists have constructed a curve showing how
often meteoroids of a given size might be expected to hit Earth. The
curve predicted swarms of mid-size objects in about the numbers now
being inferred from the military satellite records. The new data, in
turn, support the validity of the curve that predicted them and
increase confidence that the other end of the curve can help estimate
the frequency of truly catastrophic events.

Dr. Clark R. Chapman, a senior scientist at the Planetary Science
Institute, based in Tucson, cautioned that new disclosures and the raw
data on which they are based had to be carefully analyzed before their
soundness could be ascertained.

"I and most of my colleagues would like to see the data, not just
the conclusions," he said. "So far it's more than we've seen before,
but I'm not going to give it too much weight until I know more about
it."

In the 20th century, the most celebrated collision between Earth and
an object from space occurred in 1908 in the Tunguska region of
Siberia. The object exploded in the atmosphere with a force of some 20
hydrogen bombs, its shock waves flattening hundreds of square miles of
forest and registering on scientific instruments around the globe.

Reports of similar encounters over the decades have been rare.
A near miss occurred in 1972 when a large asteroid, estimated at up to
260 feet in diameter, or nearly the length of a football field, sped
through the upper atmosphere over the northern United States and Canada, blazing across the sky in a daylight fireball witnessed by thousands of people before it re-entered space.

Unknown to the public, military satellites in space for decades have been seeing large numbers of atmospheric blasts.The main witnesses have been early-warning craft known as D.S.P., for
Defense Support Program, which perch in orbits some 23,300 miles above
Earth, their telescopes searching the globe for signs of rocket attack.
The sensors are said to mainly work in the infrared part of the
electromagnetic spectrum, which is the domain in which heat is
registered.

"D.S.P. has been seeing these for a long time and ignoring them,"
said Dr. Gregory H. Canavan, a physicist at the Los Alamos National
Laboratory in New Mexico who works and publishes in the Earth-impact
field.

Effort to Gather Data

The first effort to collect such data systematically began in 1975,
Dr. Tagliaferri said. One motivation was to help the Defense Department
distinguish between natural explosions and those caused by humans. The
collection process was systematic but informal. Magnetic tapes on which
raw data existed were usually recycled, so that the preservation of
information depended largely on the skills and interests of individual
Defense Support Program watch officers, who scanned the sky for trouble.

The importance of the analytical effort was driven home within the Pentagon bureaucracy in
1979, when a mysterious flash occurred over the Indian Ocean. Its
geographical proximity to South Africa raised questions about whether
it was a clandestine nuclear test, with the issue being hotly debated
for years. Another flash near South Africa in December 1980 prompted
another round of debate, with Pentagon analysts concluding two months later that the flash was evidently from a meteor.

The new report on the 136 atmospheric explosions is the first
overview of this informational treasure trove. The report identifies no
satellite system by name, but says at least two types were involved: an
infrared system to search for rocket launchings, and a visible-light
system to detect nuclear bursts. The former system is apparently
operated by the Air Force and the latter one by the Energy Department.

The co-authors of chapter, in addition to Dr. Tagliaferri, are Dr.
Richard Spalding and Dr. Cliff Jacobs of the Energy Department's Sandia
National Laboratories in Albuquerque, N.M., Col. Simon P. Worden of the
Air Force and Dr. Adam Erlich of Comprehensive Technologies
International in Arlington, Va., a military contractor.

Colonel Worden, who also holds a doctorate in astronomy, is credited
as being the main force behind the declassification of the secret data.

In an interview, Dr. Tagliaferri said the satellite systems, which
he declined to name, were built and operated so they had about a 20
percent chance of seeing the one- or two-second flash of a meteoroid
explosion anywhere around the globe. That uncertainty in trying to
understand the overall rate of planetary bombardment was compounded, he
said, by that fact that recording the data was usually an on-again,
off-again affair.

Estimate on Incidents

"My sense is that there are about 10 times as many events" as were recorded, he said. "But there is no way to know."

He said calculations showed that the 136 blasts ranged from the
equivalent of roughly 500 tons of high explosives up to 15,000 tons,
the latter amountbeing the force of the nuclear bomb that leveled
Hiroshima. The most accurately measured blasts were viewed by multiple
satellite sensors. Of these, according to the book chapter,
the brightest occurred on April 15, 1988, high above Indonesia. Its
power was calculated to be equal to 5,000 tons of high explosives.

An observer on the ground 20 miles away would have seen a flash of
light the brightness of the sun, the chapter says. Dr. Tagliaferri
added that he knew of no reports of the explosion from Indonesia. It
occurred at 11:20 A.M.

Another large explosion viewed by more than one satellite occurred on Oct. 1, 1990, over the Pacific Ocean and had a force larger than 1,000 tons of high explosives. A subsequent analysis concluded that the exploding object had been a stony, 100-ton asteroid.

"The Central Pacific asteroid detonation was originally collected as
a potential nuclear event, and it took several months, using the most
sophisticated sensors and algorithms available, to determine the
detonation's true source," a manuscript of the book chapter states. "This
suggests that developing nations and potential combatants worldwide,
with considerably less sophisticated equipment, might potentially
misidentify one of these detonations as a nuclear attack and
'retaliate' against the country's most likely aggressor."

In an interview, Dr. Tagliaferri noted that some widely reported events have been missed by the military satellites. On
Oct. 9, 1992, for instance, a bright streak across the East Coast sky
ended in Peekskill, N.Y., coming to Earth to slam through a 1980 red
Chevrolet Malibu. The resulting hole went though the trunk and the gas
tank. Found beneath the car was a smoking, football-size rock in a
crater six inches deep.

[On Tuesday, February 5], lost within the orange glow of the setting
sun, a newly discovered asteroid passed within 84,000 miles of our
planet, just a third of the distance to the Moon, and barely anyone
noticed. A sharp-eyed skywatcher with a good pair of binoculars might
have seen the unfamiliar object gliding silently through Aquarius. But
did they know what they were seeing was a very unexpected asteroid?
Would they have understood just how close it really was?

Near-Earth Object, 2008 CT1, was discovered only two days before [the] close pass by the Lincoln Near-Earth Asteroid Research project,
an MIT project funded by the USAF and NASA committed to discovering
space rocks that orbit near Earth. Using robotic telescopes located at
New Mexico's White Sands Missile Range, the project has contributed
nearly 70% of world-wide Near-Earth Asteroid discoveries since
beginning operations in 1998.

[The] asteroid, estimated between 8m - 15m wide, sounds small as
asteroids go, but recent studies suggest that even smaller rocks can be
devastating. The cause of the Tunguska Event of the early 20th Century
is now believed to be a 35m rock that never even touched the surface.
The new hypothesis suggests it exploded a few miles above the ground,
creating a shockwave that wreaked havoc on the ground beneath. Just
last September, the Earth-impacting meteorite that created a 13m wide crater in Peru is estimated to have been just 0.2m - 2m wide.

[This most recent asteroid] pass was very close on a cosmic scale - and its late discovery makes it an even closer call. Asteroid 2007 TU24 got a lot of media attention last week, but we knew that one was coming and where to look. We even caught a glimpse on Slooh.
With all the telescopes pointed to the heavens, watching the skies for
that next great impactor, there are still rocks that slip by unnoticed.
Observing close encounters with known asteroids is a great opportunity
to learn more about our Solar System, and how to spot future Near Earth
Objects - even those not on our radar yet.

Joseph
Harrison, 4, of Pasadena looks at a 379-pound nickel-iron meteorite
that has been added to the permanent collection in the Kidspace
Children Museum's Boone Nature Exchange center. The meteorite landed in
Argentina 10,000 years ago before being discovered by conquistadors in
1570. It belonged to a local private art collection in 2002 and was
donated to Kidspace Children's Museum in Pasadena in 2008.

But its significance appeared lost to schoolchildren who viewed it Wednesday.

Many of them were decidedly unimpressed by the space relic. With its
deep brown color and copper flecks, it looked like just another rock,
several kids said.

"It's just a rock. If you turn it to this side, the profile looks
like a turtle," said second-grader Roy Marquez, 8, of Jefferson
Elementary School, who spent several minutes petting the meteorite.

And even though museum officials had placed the meteorite on an
elevated platform, that wasn't enough to entice many students, who
simply ran past it. Some students even jumped on the platform before
sprinting off.

Punam Bhakta, a Kidspace off-site education lead, said the meteorite
exhibit comes at the end of the tour of the Nature Exchange, which has
plastic trays of different minerals, rocks and shells and tables to
study.

The Associated Press is reporting that the meteor that streaked
across Montana early Tuesday morning landed in eastern Washington.

A Federal Aviation Administration spokesman in Seattle says a
Horizon Airlines pilot say the meteorite hit at around 6:45 a.m. near
State Route 26 and Lind-Hatton Road in the southeast corner of Adams
County. (click here for map)

There have been no reports of damage and sheriff's dispatchers say they aren't aware of any meteorite landing in the area.

Authorities say they have been inundated with calls from Kalispell,
Plains, Missoula, Hot Springs, the Bitterroot Valley and Spokane,
Washington of a bright light in the sky Tuesday morning. Callers
described the phenomenon as bright blue in color.

Meanwhile, a Federal Aviation Administration duty officer in Seattle confirms that the streaking light in the sky was a meteor.

The officer, who would not give his name, told The Associated Press
that it was seen by pilots from Boise, Idaho, westward well into
Washington state.

Montana's News Station also received reports of a fire ball that lit
up the sky in western Montana at around 6:30 a.m. on Tuesday.

Reports have come in from Victor to Ninemile and several people in
the Blue Mountain area in Missoula have reported seeing the spectacle.

Viewers have called in to report seeing the sky light up from Ronan to between Billings and Livingston.

We talked with the National Weather Service office in Missoula and
they tell us that nothing showed up on their radar Tuesday morning, but
they received calls of the incident. They say from initial appearances
it looks like a meteor crossed the area.

Early risers across Clark County saw a meteor, described as blue or
green in color, that hit the ground in Eastern Washington around 5:45
a.m. today.

The meteor was traveling from west to east, according to witness
reports. The Associated Press reported the sighting was confirmed by
the Federal Aviation Administration in the Seattle area, and was
reported from Portland to Seattle and east to Spokane and Boise.

Travis Rood of Vancouver was driving east on McLoughlin Boulevard,
around 5:25 a.m., on his way to work. He looked up as he approached
Grand Boulevard and saw the meteor.

"It started out way high in the sky, like a basic shooting star,"
Rood said. "As it traveled eastward and downward, it just started
getting bigger and bigger.

"It went from white to bright green to white," Rood said. "It looked
like it hit in the east, and it lit up the whole sky like sheet
lightning."

A Federal Aviation Administration spokesman in Seattle, Mike Fergus,
says a Horizon Airlines pilot saw the meteorite hit earth about 5:45
a.m. Fergus says the pilot reported a flash and a burst of light near
State Route 26 and the Lind-Hatton Road in the southeast corner of
Adams County.

John Dingethal of Ridgefield described a brilliant flash of colored
light on the eastern horizon at 5:30 a.m.. "I was looking out my
second-story bedroom window and saw a round ball of intense blue light
appear suddenly, like and exploding firework," Dingethal said.

In extreme northern Clark County, near Chelatchie Prairie, Cathy
Potter reported seeing a blue-green ball of light with a small tail at
the same time. She then described "an explosion of white, blue, green
and orange similar to a transformer explosion."

Emergency crews of "Tyumen'TransGaz" removed consequences of the
gust in the main gas pipe located in the Khanty Mansiysk autonomous
area, as reported on Sunday by Emergency and Disaster Relief Ministry
of the Russian Federation.

Comment: According to the words of the witness,
there was a big explosion n Nyagan town in Siberia. The blow up was
accompanied with a sound of "jet plane landing". He commented that the
event was big.

The gust of the main gas pipe occurred in the October region
(northwest of the city Khanty Mansiysk) at 18.15 MSK on Saturday. There
are no victims or injured, as mentioned in the report on the site of
the Ministry.

A similar emergency - the break of the main gas pipe with the
subsequent fire occurred on Sunday morning in the suburb of Valdaya
(Novgorod region). There are no injuries. According to the specialists
of Emergency and Disaster Relief Ministry, possible reason for the
incident is a deformation of the pipe with the so-called "fatigue of
metals".

Jim Todd, the planetarium manager at OMSI, said some reports indicated hearing a sonic boom that rattled windows. He said the fireball moved from the west to the east.

Federal Aviation Administration officials in Portland said there
were no reports of planes going down and they believe it may have been
a meteor.

In the Portland area, there were reports of a bright flash of light
being seen everywhere from Sauvie Island to Mount Tabor to Hillsboro.

Residents in the eastern Oregon cities of Baker City and Lagrande,
and the southwest Washington cities of Woodland and Goldendale, also
reported seeing the possible meteor.

Meanwhile, in Washington, a Federal Aviation Administration
spokesman said a pilot reported seeing a burst of light in Adams
County. Adams County sheriff's deputies and Washington State Patrol
said there were no reports of an impact.

FOX 12 wants to hear from anyone who may have pictures, video or
surveillance cameras that may have caught the fireball. Contact the FOX
12 newsroom by e-mailing FOX12news@kptv.com.

Bright flash spotted at about 5:30 a.m. as far west as Tillamook, as far east as Idaho

A bright white streak in the sky early Tuesday was seen all across
the Portland area, triggering dozens of calls to local 9-1-1
dispatchers.

It was most likely a meteorite.

The white flash was seen in the eastern sky, streaking from north to south around 5:30 a.m.

Dick Pugh, scientist with Cascadia Meteorite Lab at Portland State
University, tells KPAM 860 radio it was probably "a fireball containing
pieces of rock material coming into the atmosphere from space exploding
at the end."

Pugh says meteorites, which travel 50,000 miles an hour, usually light up the sky around 90 miles above earth.

At Portland International Airport, air traffic controllers reported seeing a flash reflected in their windows.

Puge says if someone heard a sonic boom, it would indicate some
meteorite pieces actually landed. So far, there have been no reports of
falling pieces.

Meteorites from the Moon and Mars give earthbound scientists free
rock samples from other worlds. Now Brett Gladman and Jaime Coffey
(University of British Columbia, Vancouver) say we should expect a few
meteorites from Mercury too.

Gladman and Coffey conducted computer simulations of what happens
after asteroids and comets slam into the innermost planet and kick
debris into space. Past studies assumed that rocks knocked off Mercury
weren't getting away with much more than its escape velocity of 2.6
miles (4.2 km) per second. That's too slow to climb away from the Sun
and make it out to Earth.

Taken
by Messenger on January 14, 2008, from about 17,000 miles away, this
view of a gibbous Mercury shows about half of the area not photographed
by Mariner 10 in 1974 - 75. The heavily cratered landscape is
reminiscent of other areas previously seen. The broad circular plain
toward upper right, appearing brighter than its surroundings in this
red-light view, marks the interior of Caloris basin, a huge impact scar
more than 800 miles across.

But some previous assumptions were wrong, says Gladman, because the
collisional circumstances at Mercury are "very different than anywhere
else." The Sun's innermost planet speeds through space with a mean
velocity of 30 miles (48 km) per second. Furthermore, asteroids and
comets crossing Mercury's orbit also travel fast. So impactors strike
the planet at speeds 5 to 15 times its escape velocity, and ejecta can
rocket off the surface traveling much faster than had been assumed.

The new study, which has been submitted to Meteoritics and Planetary Science,
concludes that up to 5% of this high-speed debris from Mercury reaches
Earth - a third to a half of the delivery rate of meteorites from Mars.
Gladman notes that roughly a half dozen samples of Mercury might
already be sitting in meteorite collections worldwide.

But how would an interplanetary prospector recognize that a stone
really is from the innermost planet? Some planetary geologists think a
rare class of meteorites called angrites might be good candidates,
though others disagree. Gladman cautions, "Until you have some kind of
ground truth, it's very difficult to make those claims." He says
scientists need more information about the composition of Mercury's
surface to find matches with suspicious meteorites.

Rocks
from Mercury? These pieces of the meteorite known as Northwest Africa
2999 are angrites, a rare type that some specialists believe may
represent samples of Mercury's surface. The total weight of these is
392 grams (about 14 ounces); the small cube is 1 cm on a side.

Fortunately, the Messenger spacecraft has begun exploring the
planet. Messenger flew past Mercury in January and will go into orbit
in 2011. It should provide the data that will confirm or refute
candidate meteorites from Mercury.

Although the chances of an asteroid hitting Earth appear to be small
for any given year, the consequences of such an event would be
monumental. The science community has come up with some ideas and
proposals for ways to mitigate the threat of an incoming asteroid
hitting the Earth. Some proposals suggest almost Hollywood type
theatrics of launching nuclear weapons to destroy the asteroid, or
slamming a spacecraft into a Near Earth Object to blow it apart. But
other ideas employ more simple and elegant propositions to merely alter
the trajectory of the space rock. One such plan uses a two-piece solar
sail called a solar photon thruster that draws on solar energy and
resources from the asteroid itself.

Physicist Gregory Matloff has been working with NASA's Marshall
Spaceflight Center to study the two-sail solar photon thruster which
uses concentrated solar energy. One of the sails, a large parabolic
collector sail would constantly face the sun and direct reflected
sunlight onto a smaller, moveable second thruster sail that would beam
concentrated sunlight against the surface of an asteroid. In theory,
the beam would vaporize an area on the surface to create a "jet" of
materials that would serve as a propulsion system to alter the
trajectory of the Near Earth Object (NEO.)

Changing the trajectory of a NEO exploits the fact that both the
Earth and the impactor are in orbit. An impact occurs when both reach
the same point in space at the same time. Since the Earth is
approximately 12,750 km in diameter and moves at about 30 km per second
in its orbit, it travels a distance of one planetary diameter in about
seven minutes. The course of the object would be altered, or either
delayed or advanced and cause it to miss the Earth.

But of course, the arrival time of the impactor must be known very
accurately in order to forecast the impact at all, and to determine how
to affect its velocity.

Additionally, the solar photon thruster's performance would vary
depending on the unique makeup of each NEO. For example, asteroids with
a greater density, radius or rate of rotation would cause decreased
performance of the solar photon thruster in acceleration and deflection.

Even though the solar photon thruster appears to be efficient in its
performance, Matloff said that more than half of the solar energy
delivered to the "hotspot" on the NEO would not be available to
vaporize and accelerate the jet due to other thermodynamic processes
such as conduction, convection, and radiation. As expected, a larger
collector sail radius would increase the amount of energy available,
and would increase acceleration of the NEO. Matloff said this system
allows the sail craft to "tack" against the solar-photon breeze at a
larger angle than conventional single solar sails can achieve.

This system of sails would not be attached to the NEO, but would be
kept nearby the NEO "on station" either with its own thrusting
capability or by auxiliary electric propulsion. More studies would be
needed to ascertain if a supplementary propulsion system would be
necessary.

The sails used in the study were both inflatable. However, Matloff
believes it might be worth considering a small rigid thruster sail,
which might simplify deployment and reduce occultation.

Once considered just your average single asteroid, 2001 SN263 has
now been revealed as the first near-Earth triple asteroid ever found.
The asteroid -- with three bodies orbiting each other -- was discovered
this week by astronomers using the radar telescope at the National
Science Foundation's (NSF) Arecibo Observatory in Puerto Rico.

2001 SN263 has now been revealed as the first near-Earth triple asteroid ever found. -

Cornell and Arecibo astronomer Michael C. Nolan said he and his
colleagues made the discovery when they obtained radar images Feb. 11.
The group subsequently took more images to learn that the three objects
-- about 7 million miles from Earth -- are rotating around each other.

The main, central body is spherical with a diameter of roughly 1.5
miles (2 kilometers), while the larger of the two moons is about half
that size. The smallest object is about 1,000 feet across, or about the
size of the Arecibo telescope.

Other triple asteroids exist in the asteroid belt (between Mars and
Jupiter) and beyond, but this is the first near-Earth system where the
actual shapes of objects can be clearly seen.

The Arecibo telescope is operated for the NSF by Cornell's National Astronomy and Ionosphere Center.

"This discovery has extremely important implications for ideas about
the origins of near-Earth asteroids and the processes responsible for
their physical properties," said Nolan. "Double, or binary, asteroid
systems are known to be fairly common: about one in six near-Earth
asteroids is a binary, but this is the first near-Earth triple system
to be discovered."

The triple asteroid was first discovered visually Sept. 19, 2001, by
the Lincoln Near Earth Asteroid Research (LINEAR) project, part of the
Massachusetts Institute of Technology's Lincoln Laboratory. The orbits
of binary-- and now triple -- asteroid systems unveil the mass and
allow astronomers to assess whether they are stable over millennia or
have formed very recently. Previous radar investigations of binary
near-Earth asteroids have disclosed extraordinary physical and
dynamical characteristics.

Nolan said this discovery prompts several important questions: Are
the objects orbiting in the same plane? How rapidly are the orbits
changing with time? Did the moons form when this asteroid formed in the
main asteroid belt, or after it arrived in near-Earth space?

Because of the small sizes and irregularly shaped components, 2001
SN263 should offer unique insights relative to the much larger triple
systems in the main asteroid belt, said Nolan. "Examining the orbits of
the moons as we continue to observe 2001 SN263 over the next few weeks
may allow us to determine the density of the asteroid and type of
material from which it is made," he said. "We will also be studying its
shape, surface features and regolith [blanketing material] properties."

Radar observations by the Arecibo Observatory can image a much
larger fraction of the population of near-Earth asteroids than
spacecraft. For example, Arecibo has discovered more than half of the
near-Earth binary asteroid systems discovered since 1999. Continued
observations will undoubtedly lead to the discovery of new classes of
objects, such as this triple system. While the Arecibo telescope is
capable of these investigations, the future of the radar program and
the entire telescope are in considerable doubt due to NSF budget cuts.

satellite images of southern Iraq have revealed a two-mile-wide impact crater caused by a meteor

Studies of satellite images of southern Iraq have revealed a
two-mile-wide circular depression which scientists say bears all the
hallmarks of an impact crater. If confirmed, it would point to the
Middle East being struck by a meteor with the violence equivalent to
hundreds of nuclear bombs.

Today's crater lies on what would have been shallow sea 4,000 years
ago, and any impact would have caused devastating fires and flooding.

The catastrophic effect of these could explain the mystery of why so
many early cultures went into sudden decline around 2300 BC.

They include the demise of the Akkad culture of central Iraq, with
its mysterious semi-mythological emperor Sargon; the end of the fifth
dynasty of Egypt's Old Kingdom, following the building of the Great
Pyramids and the sudden disappearance of hundreds of early settlements
in the Holy Land.

Until now, archaeologists have put forward a host of separate
explanations for these events, from local wars to environmental
changes. Recently, some astronomers have suggested that meteor impacts
could explain such historical mysteries.

The crater's faint outline was found by Dr Sharad Master, a
geologist at the University of Witwatersrand, Johannesburg, on
satellite images of the Al 'Amarah region, about 10 miles north-west of
the confluence of the Tigris and Euphrates and home of the Marsh Arabs.

"It was a purely accidental discovery," Dr Master told The Telegraph
last week. "I was reading a magazine article about the canal-building
projects of Saddam Hussein, and there was a photograph showing lots of
formations - one of which was very, very circular."

Detailed analysis of other satellite images taken since the
mid-1980s showed that for many years the crater contained a small lake.

The draining of the region, as part of Saddam's campaign against the
Marsh Arabs, has since caused the lake to recede, revealing a ring-like
ridge inside the larger bowl-like depression - a classic feature of
meteor impact craters.

The crater also appears to be, in geological terms, very recent. Dr
Master said: "The sediments in this region are very young, so whatever
caused the crater-like structure, it must have happened within the past
6,000 years."

Reporting his finding in the latest issue of the journal Meteoritics
& Planetary Science, Dr Master suggests that a recent meteor impact
is the most plausible explanation for the structure.

A survey of the crater itself could reveal tell-tale melted rock.
"If we could find fragments of impact glass, we could date them using
radioactive dating techniques," he said.

A date of around 2300 BC for the impact may also cast new light on
the legend of Gilgamesh, dating from the same period. The legend talks
of "the Seven Judges of Hell", who raised their torches, lighting the
land with flame, and a storm that turned day into night, "smashed the
land like a cup", and flooded the area.

The discovery of the crater has sparked great interest among scientists.

Dr Benny Peiser, who lectures on the effects of meteor impacts at
John Moores University, Liverpool, said it was one of the most
significant discoveries in recent years and would corroborate research
he and others have done.

He said that craters recently found in Argentina date from around
the same period - suggesting that the Earth may have been hit by a
shower of large meteors at about the same time.

Residents of Uttar Pradesh's Kaushambi District are a worried lot as
the area has been receiving acid rain for the past few days.

Residents of Uttar Pradesh's Kaushambi District are a worried lot as
the area has been receiving acid rain for the past few days.

The stinking yellow coloured rain, reportedly each drop having half
a centimeter diameter, has been giving nightmares to the residents of
the area.

They say that the yellow rain has been falling mostly during the night though sometimes it falls during the daytime as well.

"For the past few days, we have been receiving yellow rain. We
received more yellow rain in the night as compared to the day time
although we saw yellow rain in the day as well. I have never seen
anything like this in my life. Everybody is afraid," said Pushapa
Manauri, a resident.

The yellow rain has been continuing for the past one-month. Experts say the yellow rain is actually acid rain.

"Chemicals get mixed with the moisture in the air by a chemical
process and become acidic. This acid in the air gets mixed with
dewdrops and falls on the ground. This is called acid rain. Since it is
yellow in colour, it is called yellow rain. This acid rain has many
unfavourable consequences," said S.S Ojha, Professor, Allahabad
University.

This yellow coloured rain was first received in Kaushambi last year during the summer season.

Since then, it has become a cause of concern for the people who are worried about the unfavourable consequences of this rain.

On 23 March 1989, asteroid 1989FC (with the potential impact
energy of over 1000 megatons, roughly the equivalent a thousand of the
most powerful nuclear bombs) missed Earth by about six hours [Freedman
1995]. We first saw this fellow after closest approach. If 1989FC had
come in six hours later most of us would have been killed with zero
warning.

There are two things you need to know about asteroids:

* Asteroids can make us extinct (the threat).

* Asteroids can make us rich and provide homes for trillions of people (the promise).

The Promise

There are vast numbers of asteroids in near-Earth orbits, some of
which are easier to access than the Moon. The potential mineral wealth
of these asteroids is so great that huge profits could be made once we
can start mining them for materials to be sold to markets on Earth.
Like space solar power, this is one of the potential revenue sources
for the large startup costs for the first space settlements.

Asteroids can also be an enormous boon to orbital settlements.
Orbital settlements must import their materials from either the Moon or
asteroids. Diverting a few small (30-70 meter diameter) asteroids into
Earth orbit could supply all the materials needed for early orbital
settlement development.

While early orbital settlements may well be in Earth orbit,
eventually humanity will spread out across the solar system. Then
asteroids become prime targets for new settlements. Hollowing out a
large, solid asteroid and building homes inside has great appeal. Such
a settlement will have ample materials in the form of the asteroid
itself, and the large mass of the asteroid provides immediate and
substantial radiation protection. With a little care radiation levels
could be less than on Earth.

Settlement of a large asteroid could start with a relatively small
tunnel, providing a home for workers that could be gradually extended
over time to build large open spaces and wonderful living areas with a
complex geometry, providing endless, safe exploration possibilities for
the children.

While some asteroids are believed to be solid enough to be hollowed
out for living space, others are known to be 'rubble-piles,' barely
held together by their weak gravity. While such asteroids cannot be
hollowed out for living in, they are much easier to mine to provide
materials for large numbers of orbital settlements.

The vast material resources of the asteroid belt beyond Mars may eventually provide home for the bulk of humanity.

The Threat

If we don't do something, sooner or later Earth will be hit by an
asteroid large enough to kill all or most of us. That includes the
plants and animals, not just people. Maybe this won't happen for millions of years. Maybe in 15 minutes. We don't know.

We have been warned. On 23 March 1989, asteroid 1989FC (with
the potential impact energy of over 1000 megatons, roughly the
equivalent a thousand of the most powerful nuclear bombs) missed Earth
by about six hours [Freedman 1995]. We first saw this fellow after
closest approach. If 1989FC had come in six hours later most of us
would have been killed with zero warning.

We are hit by thousands of smaller asteroids every year and we don't see any of them before the collision.

In October of 1990 a very small asteroid struck the Pacific Ocean
with a blast about the size of the first atomic bomb (the one that
leveled Hiroshima, Japan, killing roughly 200,000 people in seconds).
If this asteroid had arrived ten hours later it would have struck in
the middle of more than a million U.S. and Iraqi soldiers preparing for
war. How would America have reacted to what looked like an Iraqi
nuclear attack? Hiroshima-sized explosions due to asteroids actually
occur in the Earth's atmosphere about once a month [Lewis 1996b], but
are seldom seen because most of the Earth is unpopulated. The data
comes from Air Force satellites designed to look for nuclear explosions.

In 1908 a small asteroid (perhaps 50 meters across) hit Tunguska,
Siberia and flattened 60 million trees. That asteroid was so small it
never even hit the ground, just exploded in mid-air. If it had arrived
four hours and fifty-two minutes later it could have hit St. Petersburg
[Lewis 1996b]. At the time St. Petersburg was the capital of Russia
with a population of a few hundred thousand. The city would have ceased
to exist. As it was, dust from the blast lit up the skies of Europe for
days. Asteroid strikes this size probably happen about once
every hundred years. However, this is just an average. Just because we
got hit once doesn't mean we're safe for another hundred years. Indeed,
there was another Tunguska-class strike in the Brazilian rain forest on
13 August 1930 [Lewis 1996b].

There are about 1,000 asteroids a kilometer or more in diameter that cross Earth's orbit (the path Earth takes around the Sun). About a third of these will eventually hit Earth [Lewis 1996a].An asteroid strike this large can be reasonably expected to kill a
billion people or so, depending on where it hits. A strike in China or
India would kill more, in Antarctica less. Even a strike in the ocean
would create a tsunami so enormous most people living near the coast
would be drowned. A strike of this size is expected about once every
300,000 years or so.

It's not just Earth. In 1178 our Moon was hit by an asteroid
creating a 120,000 megaton explosion (about six times the force of
Earth's entire atomic arsenal). The collision dug a 20 km (12 mile)
crater. This strike was recorded by a monk in Canterbury, England. We
are extremely lucky it didn't hit us. The Moon is a smaller target and
has much less gravity to attract an impactor. If a 120,000 megaton
blast had hit the Earth our history would have been dramatically
different. We're just lucky that one hit the Moon instead.

The most recent large strike also missed Earth. In July 1994 the
comet Shoemaker-Levy 9 plowed into Jupiter. The comet broke up into
roughly 20 large pieces before contact, but when the pieces hit they
left a string of enormous explosions clearly visible to our telescopes.
The scale of the destruction was staggering. Each impact was the
equivalent of about 10 million megatons of TNT.

Sixty-five million years ago a huge asteroid several kilometers
across slammed into the Yucatan Peninsula in Mexico. This is the event
that caused the extinction of the dinosaurs (and many other species).
The explosion was the equivalent of about 200 million megatons of
dynamite, about the equivalent of all 20 pieces of Shoemaker-Levy. The
blast turned the air around it into plasma - a material so hot
electrons are ripped from the atomic nucleus and molecules cannot
exist. This is the stuff the Sun is made of. Enormous quantities of
red-hot materials were thrown into space, most of which rained down
worldwide burning literally the entire planet to a crisp. Anything not
underground or underwater was killed. This scenario has been repeated
over and over, perhaps once every 100 million years or so. Each
collision killed up to 95% of all species on Earth. As many as
two-thirds of all species that ever existed may have been terminated by
asteroids hitting the Earth.

We know about the asteroid that killed the dinosaurs because we
found the crater. But what happens when an asteroid hits the ocean?
After all, oceans cover two-thirds of the Earth's surface, and most
asteroid strikes are in water. Unless the asteroid is very large there
won't be a crater. However, if you drop a rock into a lake it makes
waves. The larger the rock the bigger the wave. Drop a 400 meter (four
football fields) diameter asteroid into the Atlantic Ocean and you get
a tsunami 60 meters (yards) high [Willoughby and McGuire 1995].

The only way to eliminate the threat of asteroids is to detect them
and divert them. Right now we depend on a trickle of government funding
for this. Detection of Earth-threatening rocks is very far from
complete. At the present rate it will take years before we find just
90% of them.

A vigorous space settlement civilization based on asteroidal
materials would have enormous economic incentives to find and utilize
every asteroid passing anywhere near Earth. They would be found,
diverted, and mined for their materials. This would defuse the threat,
make an awful lot of people extremely rich, and provide lovely homes to
even more people.

What a deal.

References

[Freedman 1995] George Friedman, "The Increasing Recognition of
Near-Earth-Objects (NEOs)," Space Manufacturing 10: Pathways to the
High Frontier, Proceedings of the Twelfth SSI-Princeton Conference, 4-7
May 1995, edited by Barbara Faughnan, American Institute of Aeronautics
and Astronautics (AIAA), pages 157-164.

The West has become 500 percent dustier in
the past two centuries due to westward U.S. expansion and accompanying
human activity beginning in the 1800s, according to a new study led by
the University of Colorado at Boulder.

Sediment records from dust blown into alpine lakes in southwest
Colorado's San Juan Mountains over millennia indicates the sharp rise
in dust deposits coincided with railroad, ranching and livestock
activity in the middle of the last century, said geological sciences
Assistant Professor Jason Neff, lead author on the study. The results
have implications ranging from ecosystem alteration to human health, he
said.

"From about 1860 to 1900, the dust deposition rates shot up
so high that we initially thought there was a mistake in our data,"
said Neff. "But the evidence clearly shows the western U.S.
had it's own Dust Bowl beginning in the 1800s when the railroads went
in and cattle and sheep were introduced into the rangelands."

A paper on the research funded by the Andrew W. Mellon Foundation was published in the Feb. 24 issue of Nature Geoscience.
Co-authors included CU-Boulder's Ashley Ballantyne, Lang Farmer and
Corey Lawrence, Cornell University's Natalie Mahowald, the University
of Arizona's Jessica Conroy and Jonathan Overpeck, Christopher Landry
of the Center of Snow and Avalanche Studies in Silverton, Colo., the
University of Utah's Tom Painter and the U.S. Geological Survey's
Richard Reynolds.

The study indicates "dust fall" in the West over the past
century was five to seven times heavier than at any time in the
previous 5,000 years, said Neff, who is also a faculty member in
CU-Boulder's Environmental Studies Program. While some
fine-grained dust from Asia periodically falls on Colorado's San Juans,
the abundance of larger-sized dust particles in the lake sediments
there indicates most of the dust originated regionally in the
Southwest, said the authors.

While droughts can trigger erosion and increased dust deposition,
western U.S. droughts during the past two centuries have been
relatively mild compared to droughts over the past 2,000 years, Neff
said. Instead, the increased dustiness in the West coincides with
intensive land use, primarily grazing, according to radiocarbon dating
and lead isotope analysis of soil cores retrieved from lakebeds, he
said.

"There were an estimated 40 million head of livestock on the western
rangeland during the turn of the century, causing a massive and
systematic degradation of the ecosystems," said Neff. The 1934 Taylor
Grazing Act that imposed restrictions on western grazing lands
coincided with a decrease in accumulation rates of the San Juan lake
sediments in the study -- a decrease that continues to today, he said.

The study also shows more than a five-fold increase in nutrients and
minerals in the lakebed sediments during the last 150 years, said Neff.
Increases in nitrogen, phosphorus, potassium, calcium and magnesium --
byproducts of ranching, mining and agricultural activity - have been
shown to change water alkalinity, aquatic productivity and nutrient
cycling.

In the Niwot Ridge alpine region west of Boulder, for example,
CU-Boulder researchers have observed increased algal growth in streams
and lakes as a result of rising nitrogen deposition, as well as changes
in the composition and diversity of wildflowers on the tundra. "Because
these types of inputs have the potential to increase plant growth, the
ultimate outcome of such depositions could change the fabric of our
ecosystems," said Neff.

The San Juan lakes are located in an area dominated by rocky talus
slopes with little soil and vegetation at about 13,000 feet in
elevation and are located downwind of several major U.S. deserts like
the Colorado Plateau and the Mojave. The site was chosen in part
because the San Juans experience frequent wintertime dust deposition
events -- usually between four to seven episodes annually, Neff said.

A study published in Geophysical Research Letters in 2007
involving co-authors of the Nature Geoscience paper, including Neff,
showed wind-blown dust from disturbed lands in the Southwest shortened
the duration of San Juan mountain snow cover by roughly a month. "The
dust we see in these lakes is the same dust that causes earlier spring
snowmelt here, so we can now definitively say that humans are in large
part responsible for this melt," said Neff.

"There seems to be a perception that dusty conditions in the West
are just the nature of the region," said Neff. "We have shown here that
the increase in dust since the 1800s is a direct result of human
activity and not part of the natural system."

Comment: The
researchers present a reasonable explanation for a dust increase, but
we want to offer additional information for your consideration.

"It has been suggested that the current "climate change" issues are due to the earth moving through cosmic dust clouds. It could even be that such things as "chemtrails" are a result of such dust loading in the upper atmosphere."

Clube suggests that the reason for the climate issues are
that the earth moves into a "band" of dust long before it begins to
encounter impactors and that climate cooling itself is a precursor to
more catastrophic activity.

Okay, now let's take a look at Victor Clube's summary of the problem. He writes:

Asteroid strikes, though important, are not the most serious short-term risk to mankind or civilization

Every 5-10 generations or so, for about a generation, mankind is
subject to an increased risk of global insult through another kind of
cosmic agency.

This cosmic agency is a "Shoemaker-Levy type" train of cometary
debris resulting in sequences of terrestrial encounters with sub-km
meteoroids.

While the resulting risk is ~ 10%, the global insults take the form of (a) multiple multi-megaton bombardment, (b) climatic deterioration through stratospheric dust-loading, not excluding ice-age, and (c) consequent uncontrolled disease/plague.

Subsequently perceived as pointless, such transitions are commonly
an embarrassment to national elites even to the extent that historical
and astronomical evidence of the risk are abominated and suppressed.

Upon revival of the risk, however, such "enlightenment" becomes an
inducement to violent transition since historical and astronomical
evidence are then in demand.

Such change and change about in addition to the insult is evidently
self-defeating and calls for a procedure to eliminate the risk.

The very short lead-time commonly associated with the detection of
sum-km meteoroids approaching the Earth implies countering procedures
which differ from those associated with catalogued km-plus asteroids
and comets.

So, the question is: if there is even a 10 % chance that we are
facing a Shoemaker-Levy type event, why isn't anybody doing anything
about it?

The initial plan would put the craft into space in 2020 where it
will approach the asteroid and launch two penetrating devices. These
will deliver equipment including a specially adapted camera,
transmitter and antenna. Air bags will be used to safely deliver the
equipment and also will be attached with solar panels to power the
equipment.

The equipment will collect data on the location and composition of
the asteroid and relay it back to Earth. If needed the spacecraft can
again approach the asteroid in 2025 to divert the asteroid from its
path using the gravitational pull of the spacecraft. The asteroid will
pass the Earth in 2029 before returning in 2036 and the team aim to
change the path of the asteroid during this pass.

According to Dr Alexander Kogan, who guided the students, the craft
will use its ion thrusters to hover 200-300m from the asteroid for four
months. Using the mass of the spacecraft, combined with the effect of
Earths' gravity, the craft will pull the asteroid out of its previous
path.

'The spacecraft is what will make the difference,' said student Lior
Avital. 'It will divert the asteroid one kilometre and with the help of
the Earth, in seven years - 7,000km.'

Alternatives such as blasting the asteroid with a nuclear bomb were
also considered, but the group believed the danger posed by two large
asteroids or many small ones would be much greater. Diverting the
asteroid by connecting powerful motors to it was also ruled out as the
solution was deemed too expensive and complicated.

Albuquerque, N.M. - Dust from asteroids entering the atmosphere may
influence Earth's weather more than previously believed, researchers
have found.

In a study to be published this week in the journal Nature,
scientists from the Australian Antarctic Division, the University of
Western Ontario, the Aerospace Corporation, and Sandia and Los Alamos
national laboratories found evidence that dust from an asteroid burning
up as it descended through Earth's atmosphere formed a cloud of
micron-sized particles significant enough to influence local weather in
Antarctica.

The
asteroid's dust trail as seen by lidar at Davis, Antarctica. The plot
shows the strength of the vertical laser light scattered back from the
atmosphere as a function of time and altitude above mean sea level. The
dust trail, blown by the stratospheric winds, moved through the beam.

Micron-sized particles are big enough to reflect sunlight, cause local cooling, and play a major role in cloud formation, the Naturebrief observes. Longer research papers being prepared from the same
data for other journals are expected to discuss possible negative
effects on the planet's ozone layer.

"Our observations suggest that [meteors exploding] in Earth's
atmosphere could play a more important role in climate than previously
recognized," the researchers write.

Scientists had formerly paid little attention to asteroid dust,
assuming that the burnt matter disintegrated into nanometer-sized
particles that did not affect Earth's environment. Some researchers
(and science fiction writers) were more interested in the damage that
could be caused by the intact portion of a large asteroid striking
Earth.

But the size of an asteroid entering Earth's atmosphere is
significantly reduced by the fireball caused by the friction of its
passage. The mass turned to dust may be as much as 90 to 99 percent of
the original asteroid. Where does this dust go?

The uniquely well-observed descent of a particular asteroid and its resultant dust cloud gave an unexpected answer.

On Sept. 3, 2004, the space-based infrared sensors of the U.S.
Department of Defense detected an asteroid a little less than 10 meters
across, at an altitude of 75 kilometers, descending off the coast of
Antarctica. U.S. Department of Energy visible-light sensors built by
Sandia National Laboratories, a National Nuclear Security
Administration lab, also detected the intruder when it became a
fireball at approximately 56 kilometers above Earth. Five infrasound
stations, built to detect nuclear explosions anywhere in the world,
registered acoustic waves from the speeding asteroid that were analyzed
by LANL researcher Doug ReVelle. NASA's multispectral polar orbiting
sensor then picked up the debris cloud formed by the disintegrating
space rock.

Some 7.5 hours after the initial observation, a cloud of anomalous
material was detected in the upper stratosphere over Davis Station in
Antarctica by ground-based lidar.

"We noticed something unusual in the data," says Andrew Klekociuk, a
research scientist at the Australian Antarctic division. "We'd never
seen anything like this before - [a cloud that] sits vertically and
things blow through it. It had a wispy nature, with thin layers
separated by a few kilometers. Clouds are more consistent and last
longer. This one blew through in about an hour."

The cloud was too high for ordinary water-bearing clouds (32
kilometers instead of 20 km) and too warm to consist of known manmade
pollutants (55 degrees warmer than the highest expected frost point of
human-released solid cloud constituents). It could have been dust from
a solid rocket launch, but the asteroid's descent and the progress of
its resultant cloud had been too well observed and charted; the
pedigree, so to speak, of the cloud was clear.

Computer simulations agreed with sensor data that the particles'
mass, shape, and behavior identified them as meteorite constituents
roughly 10 to 20 microns in size.

Says Dee Pack of Aerospace Corporation, "This asteroid deposited
1,000 metric tons in the stratosphere in a few seconds, a sizable
perturbation." Every year, he says, 50 to 60 meter-sized asteroids hit
Earth.

Peter Brown at the University of Western Ontario, who was initially
contacted by Klekociuk, helped analyze data and did theoretical
modeling. He points out that climate modelers might have to extrapolate
from this one event to its larger implications. "[Asteroid dust could
be modeled as] the equivalent of volcanic eruptions of dust, with
atmospheric deposition from above rather than below." The new
information on micron-sized particles "have much greater implications
for [extraterrestrial visitors] like Tunguska," a reference to an
asteroid or comet that exploded 8 km above the Stony Tunguska river in
Siberia in 1908. About 2150 square kilometers were devastated, but
little formal analysis was done on the atmospheric effect of the dust
that must have been deposited in the atmosphere.

The Sandia sensors' primary function is to observe nuclear
explosions anywhere on Earth. Their evolution to include meteor
fireball observations came when Sandia researcher Dick Spalding
recognized that ground-based processing of data might be modified to
record the relatively slower flashes due to asteroids and meteoroids.
Sandia computer programmer Joe Chavez wrote the program that filtered
out signal noise caused by variations in sunlight, satellite rotation,
and changes in cloud cover to realize the additional capability. The
Sandia data constituted a basis for the energy and mass estimate of the
asteroid, says Spalding.

The capabilities of defense-related sensors to distinguish between
the explosion of a nuclear bomb and the entry into the atmosphere of an
asteroid that releases similar amounts of energy - in this case, about
13 kilotons - could provide an additional margin of world safety.
Without that information, a country that experienced a high-energy
asteroid burst that penetrated the atmosphere might provoke a military
response by leaders who are under the false impression that a nuclear
attack is underway, or lead other countries to assume a nuclear test
has occurred.

More detailed papers are slated for the Journal of Geophysical Research and the Journal of Meteoritics and Planetary Science, Pack says.

Our mission, should we choose to accept it: (1) Make up to six
billion people understand the danger that faces this world. (2) Make
them care enough. (3) Keep them caring long enough for it to matter.
(4) Give them what they need to stop what's coming.

- Larry Niven, February 20, 2004 (from a presentation at the 2004
Planetary Defense Conference, sponsored by the American Institute of
Aeronautics and Astronautics)

I. Introduction - The Threat

Planetary defense encompasses protecting the Earth from potential
destruction due to impact by a large piece of space debris.
Astronomical telescopes and deep space radar systems have verified the
existence of a large number of near Earth objects (NEOs), such as
asteroids, meteoroids, and comets that potentially could destroy most
life on Earth. Where NEOs intersect Earth's orbit, there exists a risk
of a collision. [1] An asteroid with a diameter of 1-10 km would strike
the Earth with a power rivaling the strength of a multiple warhead
attack with the most powerful thermonuclear explosives known to man.
Computational fluid dynamics studies have indicated that an ocean
strike by such an asteroid may create a gigantic tsunamithat would flood and obliterate coastal regions. Perhaps even more
significantly, a land strike may eject a massive dust cloud, rivaling
that from the most powerful volcanic explosion, which could seriously
affect climate on the scale of two to three years. It could alter our biosphereto the point that life as we know it would cease to exist. As recently
as 1998, the astronomical and astrophysics community thought that most
of the known NEOs do not pose a near-term threat, and therefore do not
present any danger to the Earth and its biosphere. However, the
relatively recent collision of the comet Shoemaker-Levy 9 with the
planet Jupiter on July 16, 1994, and continuing discoveries of
non-cataloged asteroids passing near Earth without any advanced
warning, have increased concerns. It is worthwhile to note that one
striking feature of practically every celestial body in our solar
system is the abundance of impact craters. [2]

Geological evidence and observations of planetary bodies confirm the
existence of a threat, albeit small, that Earth could one day be struck
by a comet, meteor, or asteroid on a collision course from space that
would be large enough to cause widespread destruction of modern
society. In the last 100 years, a massive impact took place in Siberia
(Tunguska, 1908) that devastated 2000 square kilometers and carried the
destructive force of 12.5 megatons of TNT. This impactor was only 60
meters in diameter. The Earth's surface still shows scars of previous
larger-scale impacts. A 100-meter diameter meteor over 20,000 years ago
is believed to have caused the Meteor Crater in Arizona. In the more
massive Cretaceous-Tertiary impact (K-T impact),
a 10-km diameter object struck off the Yucatan Peninsula some 65.5
million years ago. Scientists found the crater around 1995 using
seismic monitoring equipment designed to hunt for oil. Probably the
size of a small city, the Chicxulub impact is widely believed to have
triggered a mass dinosaur die-off, either through a global firestorm
caused by earthquakes releasing pockets of methane set afire by
lightning, or through massive long-term environmental changes. The
impact likely also triggered giant tsunamis across the ocean and
earthquakes that reverberated around the world. While such enormous
impacts are certainly infrequent, objects with diameters of
approximately 1 km can be expected to intercept the Earth every 100,000
years. [3]

Some thought and planning, therefore, is needed to provide a
reasonable level of protection against such disastrous events.
Identification and cataloging of NEOs and celestial bodies is an
important first step. Observation and tracking of small (1 km or less)
objects is a difficult task given the low albedosof the target bodies and their small size. However, accurate long-term
orbital prediction models must be developed to allow for adequate
response time. NASA and the California Institute of Technology's Jet
Propulsion Laboratory (JPL) in Pasadena, California, maintain an active
list of NEOs sorted by a weighted scale indicating their approach
distance and destructive potential (the Palermo Technical Impact Hazard
Scale). In 2003, over 10 objects were identified that passed within 1.5
times the distance from the Earth to the Moon (1 lunar distance =
384,000 km). The smallest objects in the JPL database are 20 meters in
diameter with typical NEOs in the 500-meter to 1-km diameter range.
[14, 3] Currently, the highest active object on the Palermo Technical
Impact Hazard Scale (Palermo scale) is asteroid 2004 VD17, with a
cumulative Palermo scale value of -1.06. [4]

NASA has proposed new observatories that will be able to detect even
smaller objects. For example, NASA's Revolutionary Aerospace Systems
Concepts (RASC) program conducted a study called CAPS (Comet Asteroid
Protection System) that promoted a lunar telescope installation for
conducting NEO detection research. The question remains what should be
done if a planetary impactor on a collision course with Earth is
actually confirmed. [3]

II. Categorizing the Threat

The large number of circumstances in which a NEO might threaten the
Earth can be characterized by several parameters, such as warning time;
NEO size, mass, and orbital parameters; impact location; certainty of
impact; NEO orbital class (e.g., those of the Atens, Apollo, and Amor
families of asteroids, the trans-Neptunian objects, and the comets); NEO composition; and NEO spin.

The concept of a response decision chart (see Figure 1), constructed
by researchers Peter Nicolas, Andrew Barton, Douglas Robinson, and Jean
Marc Salotti, could be applied to break down the problem into
manageable sub-categories, where each branch of the tree corresponds to
a particular class of NEO threat scenarios for which response options
would be similar. [7] Thus, for any threat scenario, it can be
determined what responses are appropriate. The aim of such a
classification tree is to provide a global tool providing more useful
information to the policy maker by laying down in a simple but
comprehensive way all possible NEO impact scenarios, consequences, and
responses. In addition to the above parameters, other parameters might
require expert scientific advice, such as detectability and
destructibility. [6]

The specific classification breakdown of the parameters of warning
time, damage potential, hit location, and responses are discussed
below. In addition, another parameter, certainty of impact, is also
addressed.

A. Warning time

The classification of 'Short' is intended for threats with less than
one year of warning time. Such scenarios exclude the development of new
space missions, allowing only ground-based responses. If the warning
time is in the scale of decades, there are many opportunities for both
space-based and Earth-based mitigation efforts. The category named
'Medium' encompasses the warning time frame from 2 to 30 years,
presenting the possibility of new space missions with existing
technology. The 'Long' warning time category encompasses all NEO impact
scenarios with the impact occurring more than 30 years in the future,
so one can only speculate about far future mitigation technologies and
approaches. [6]

B. Damage potential

This refers to the effects that an NEO would have if it impacts the
Earth. The effects are largely dependent on the size and mass of the
NEO. The 'Large' category includes all NEOs larger than 2 km since
these objects would cause very large disasters and therefore require
global response efforts. The 'Small' category is intended to include
any NEO threats that would be of local or regional significance. It is
generally thought that such NEOs can be successfully deflected or
destroyed with modern technology if there is sufficient warning time.
Excluded are the very small NEOs that would burn up in the Earth's
atmosphere (less than 30 m), since these require little or no response.
[6]

C. Response limitations

The branches at this point of the tree in Figure 1 distinguish
between the different types of space-based responses. The category
named 'Deflectable' is for NEOs that are small enough or with long
enough warning time to enable deflection of the body with sufficient
delta-v to prevent its impact with Earth. The object's accessibility
should also be taken into account. When possible, this category is the
most desirable response since it doesn't affect the Earth.
'Destructible' is a possibility for objects that are not deflectable.
In some cases the NEO is held together too weakly to be able to absorb
the energy transfer required for deflection. There are also cases where
'Partially Destructible' is a possibility. Reducing the NEO into many
smaller fragments by nuclear blasts may reduce the scale of disaster on
Earth, although it also risks spreading the effects (including nuclear
fallout) over a wider area. Finally, 'Neither' is included for the
cases where the NEO is neither destructible nor deflectable. [6]

D. Hit location

The two most important distinctions for a NEO striking the Earth's
surface are between 'Ocean' impacts and 'Land' impacts. The most
devastating possible effect of an ocean impact would be a tsunami,
which would damage coasts in the region or around the world. On the
other hand, a similar size land impact would lead to more debris and
dust being ejected into the atmosphere, likely causing more severe
climatic changes. Accurate prediction of the impact location is not
always possible since it depends on accurate orbital parameters for the
NEO. In some cases, data will be insufficient to determine whether the
NEO will hit the land or the ocean (due to long warning times,
incomplete orbital observations, etc.). A dispersed impact zone
including both ocean and land regions is also possible. Furthermore,
the presence of the Earth's atmosphere may also lead to dispersion of
the body over a wide area. [6]

E. Certainty of impact

Another important tool for categorizing the Earth impact hazard associated with newly discovered NEOs is the TorinoScale, which is equivalent to the "Richter Scale" but for NEOs. This
scale was created by Professor Richard P. Binzel at the Massachusetts
Institute of Technology and revised at an international conference on
NEOs held in Torino, Italy, in June 1999. The Torino scale utilizes
numbers that range from 0 to 10, where 0 indicates an object that has a
zero or negligibly small chance of collision with the Earth, or that is
too small to penetrate the Earth's atmosphere intact in the event that
a collision does occur. A 10 indicates that a collision is certain, and
the impacting object is so large that it is capable of precipitating a
global disaster. An object is assigned a value based on its collision
probability and its kinetic energy (proportional to its mass times the
square of its encounter velocity). [6]

III. Some Possible Response Options

For all we know, a large asteroid may be heading this way right
now, and you'll never get this [conversation] on the air. The danger of
asteroid or comet impact is one of the best reasons for getting into
space. I'm very fond of quoting my friend Larry Niven: 'The dinosaurs
became extinct because they didn't have a space program.'And if we
become extinct because we don't have a space program, it'll serve us
right!

-Arthur C. Clarke

Deflecting or destroying a NEO in space is still in the realm of
science fiction. However, if an impact does occur, many steps can be
taken on Earth to mitigate its effects. It would be best, of course, to
avoid the initial catastrophe. The idea of the deflection strategy is
to change the orbit of the NEO in order to prevent an impact with
Earth. According to C. Gritzner deflection is the only solution in case
of a NEO larger than about 100m, because the destruction strategy might
worsen the situation. [15] However, the deflection of a NEO years ahead
of its impact requires that detection be achieved soon enough and its
orbital elements precisely computed.

Destruction - the second best strategy - refers to breaking the
object into many pieces. The destruction of the NEO body is generally
proposed when there is very little time left before impact, weeks or
months, so that any deflection would be insufficient. The timing of the
interception is crucial in the response decision process and depends on
the threat's detection time. If there is time for an interception, then
a space-based response is possible; if not, then the only solution is
to evacuate the impact location. [6]

1. Non-nuclear or Kinetic deflection: A non-nuclear novel concept
is employed to deflect an NEO. Alternatively, for kinetic deflection, a
large spacecraft or several spacecraft, or a missile, is/are sent to
impact and deflect the NEO using only kinetic energy.

2. Nuclear deflection: Nuclear explosions are triggered at a
distance, on the surface or after penetration, provoking the ejection
of rocks from the NEO, which in turn reacts by a small deflection.

3. Nuclear destruction: In some cases, the explosion might cause
the partial fragmentation or even the pulverization of the NEO.

4. Mass driver: If the action time is significant, it is possible
to land a device that would regularly eject some matter from the
asteroid and therefore slowly deflect it from its original trajectory.

5. Billiards shot: This option consists of deflecting a small
asteroid, putting it on a collision course with the Earth-threatening
NEO.

The selection of the best option depends on the time available for
action and the diameter (size) of the NEO. The effects of a large blast
near a NEO depend not only on the NEO's mass but also on its
composition and structure. For rubble-pile asteroids - loose
aggregations of rock, presumably the result of a collision - deflection
is impractical. In cases where deflection is desired, nuclear blasts
should not be triggered too close to the NEO to avoid its
fragmentation. When NEOs are too large for nuclear destruction or
deflection, the billiards shot option is theoretically possible but
remains uncertain in terms of accuracy and technical feasibility. In
this option, a small NEO's orbit is changed in order to achieve a
collision with the (larger) NEO on a collision course with Earth. This
method could deflect even 10-km-class NEOs. [6]

Particular scenarios or specifics concerning the above space-based
response strategies are discussed and/or considered below. Focus is
placed mainly on threatening near-Earth asteroids (NEAs). Near-Earth
asteroids, a subset of the NEOs, are asteroids whose orbit intersects
Earth's orbit and which may therefore pose a collision danger, as well
as being most easily accessible for spacecraft from Earth. [NEA Information]

1. Non-nuclear and kinetic deflection concepts

A. Mirror Ablation approach One method
of deflecting Earth-threatening asteroids uses a solar collector that
focuses sunlight on the surface of the asteroid. This strongly heats a
small spot, and vaporizes enough material so that the thrust from the
expanding jet of gas and dust can, over a period of years, divert the
asteroid. The primary difficulty with this scheme is the danger of
fouling of the last optical element in the system by evaporated
material. Overall, this scheme does not involve a large extension of
present technology. It is effective on comets, the orbits of which are
perturbed by forces generated in reaction to the jets of gas and dust
that emanate from their surfaces during passage through the inner solar
system [16, 17, 18].

Asteroids, by definition, do not emit such jets, and their orbits
are therefore much more predictable than those of comets.However, if
some means were found to create such comet-like jets even on asteroids,
the thrust of these jets could be used to steer a threatening asteroid
out of a collision course with the Earth. This is the basic idea behind
the Mirror Ablation approach, shown in Figure 2. Sunlight, freely
available in space, could be concentrated on the surface of the
asteroid, just as a burning glass can raise the temperature of wood and
leaves on the Earth's surface to the ignition point. If the sunlight is
sufficiently concentrated, even the surfaces of rocky asteroids may
become hot enough to evaporate and develop a steady thrust that will,
over time, impart a velocity increment sufficient to avert a collision
with the Earth. [Note 2] [8]

Figure
2. Schematic illustration of the basic components of the Mirror
Ablation Mission to deflect an Earth-threatening asteroid [8]

B. Kinetic energy (KE) projectile

This asteroid deflection technique is based on a fictitious threat
scenario. The mission objective is to prevent the collision of the
virtual 200-meter binary asteroid Athos with Earth on February 29,
2016. The detection date of the asteroid is assumed to be February 22,
2005, which gives a short span from the time of detection to the launch
date of the deflection spacecraft. The technique is based on the
momentum transfer from an impacting spacecraft on the hazardous object.
The impacting process coincides with the ejection of crater material,
where the total momentum change of the target object is the momentum of
the escaping ejecta plus the momentum carried with the projectile. For
nonporous targets the ratio between ejecta momentum and projectile momentumcan be as large as 13, whereas for porous targets this could be
decreased to 0.2, yielding a momentum enhancement factor of 14 and 1.2,
respectively. [23] In this particular scenario a momentum enhancement
factor of 3 is assumed, which was deduced from the physical properties
of Athos and experimental factors for analogous materials. [Note 3]A state-of-the-art launch system arsenal is thus envisioned that
comprises two rockets, which could both be used for KE interaction.
These are the American Delta IV Heavy and the European Ariane 5 capable
of launching 12.4 and 12 tons (planned for 2006) into geostationary transfer orbit(GTO), respectively. A KE mission opportunity is identified, which
maximizes the product of spacecraft mass and relative velocity (in
Athos' direction of flight) when impacting on Athos in April 2012. The
launch from GTO is scheduled for December 27, 2011.

A velocity change of 787 m/s, applied during perigee passage, is
required to get onto an interplanetary orbit. After a low-demanding
deep space maneuver (4 m/s) the spacecraft swings by Earth on February
15, 2012. This gravity assist from Earth enables the high energy impact with Athos on April 5, 2012. [Note 4] Since launch systems cannot be started within short intervals, the spacecraft are to be launched into geostationary transfer parking orbits,
beginning one year in advance of interplanetary transfer to Athos.
Last, but not least, it has to be ensured that the projectile shelling
will not cause fragmentation of Athos into large boulders that possibly
remain on collision course with Earth. The technology readiness level
of KE projectiles has been evaluated as high, and no technological
problems are expected. Possible development efforts could deal with the
shape and composition of a KE spacecraft. [9]

2. Nuclear Deflection Concept - An asteroid interceptor

In one particular study a conceptual design was developed for an
asteroid interceptor vehicle using a nuclear explosive. [10] The
proposed target for this mission is the 200-m asteroid threat object
Athos (see above). The proposed interceptor's basic functions include
locating the NEO, delivering a nuclear device to it, exploding the
nuclear device at the appropriate time/location, and verifying the
system's performance. In order to reduce interceptor propellant
requirements, a direct intercept approach, rather than a rendezvous
approach, was chosen in this scenario. Direct intercept permits the use
of a relatively large nuclear device, but places severe constraints on
the intercept conditions and affects the potential accuracy of weapon
delivery. This study limited the interceptor launch to existing
vehicles in order to enable a near-term deployment. An overall mission
objective is to provide opportunities for multiple shots, if necessary,
which implies that it would be useful to verify the performance of each
shot to determine if another shot is required. For this reason, it was
decided to provide a separate cruise stage on the interceptor for the
purpose of sensing the NEO and the kill vehicle that carries the
nuclear weapon, and relaying observations back to Earth. Other reasons
for including the cruise stage are a desire to lighten the kill vehicle
and the possible use of cooperative target tracking between the cruise
stage and kill vehicle.

The proposed interceptor consists of a cruise stage and a
kill-vehicle stage. The function of the cruise stage is to perform
spacecraft housekeeping for the interceptor during transit, relay data
to and from the kill vehicle during endgame, and verify system
performance during and shortly after intercept. The function of the
kill-vehicle stage is to deliver the weapon to the desired target point
and detonate. A mass goal for the entire interceptor stack of 6000 kg
is based on the launch vehicle capacity for a Delta IV Heavy and the
intercept trajectory requirements. Conceptual mass estimates for both
interceptor stages were developed using the spreadsheet-based Aerospace
Concurrent Engineering Model (CEM). [19] This model utilizes historical
spacecraft design relations and basic physical principles to
parametrically estimate space vehicle mass.

Payload capacity for the nuclear device was estimated by
systematically increasing the weapon mass until a launch mass limit of
6000 kg was reached for the entire launch stack. Based on the analysis,
the estimated weapon capacity for the proposed conceptual design is
1500 kg or an approximately 1.9 megaton yield with a warhead optimized
for neutron emission. [20] High neutron emission enables maximum
momentum transfer to the NEO target. [10]

3. Nuclear Destruction Concept - Nuclear fragmentation

The equations used to model the catastrophic fragmentation of a
near-Earth solid body asteroid derive from the work of Thomas J.
Ahrens, California Institute of Technology, and Alan W. Harris, Jet
Propulsion Laboratory, [21] based on the assumption that an explosive
device is placed deep enough below the asteroid's surface to produce
near-optimum fragmentation. The location for optimum fragmentation is
generally considered to be the target object's geometric center.

This assumes ideal destruction conditions, namely, (1) the asteroid
is a perfectly spherical homogeneous structure, (2) the explosive
charge is placed at the exact geometric center, and (3) the explosion
fractures the target body into pieces no larger than 10 meters in
diameter. Although open to debate, it is generally assumed that
fragments of this size would be much less likely than the original body
to survive entry through Earth's atmosphere. Even if any fragments did
reach the ground, the impact of these relatively small objects, spread
over a large area, would be less damaging from a global point of view
than a single massive asteroid strike.

Asteroids greater than 2 km in diameter would be considered
catastrophic to the Earth. Unfortunately, there are currently no
existing nuclear devices that could catastrophically fragment an
asteroid greater than 2 km in diameter.

One idea considered to place an explosive device at the geometric
center of an asteroid that can be destroyed (those about less than 2 km
in diameter) of the target body is to use the same technology that is
found in the " long-rod bunker buster" ordinance that the U.S. military
employs against underground facilities. This idea has the advantage of
not requiring a delta-v breaking maneuver to rendezvous with and "soft"
land on the target. Instead the outbound kinetic energy is used to bury
the device to the optimum depth. It is assumed that the explosive
device can be successfully delivered kinetically to the "center" of a
200 m diameter asteroid; anything larger may require the use of some
sort of drilling or auger device.

4. Mass Driver Concept - The Modular/Swarm Architecture

A modular architecture of smaller devices can provide the means to
build up defensive capability immediately while allowing for system
improvements and modifications over time. An approach conceptualized by
SpaceWorks Engineering, Inc. (SEI, Atlanta, Georgia) is to subtly
change the orbit of a potential impactor far from the point of impact.
Mass drivers landed on the impactor will be used to eject small pieces
of the asteroid's own mass to gradually affect its velocity. SEI
advocates the use of multiple, "small" lander spacecraft to provide a
modular, scalable, and rapid response to planetary defense.

Their solution consists of hundreds or thousands of identical
spacecraft that will intercept the target body and conduct mass
driver/ejector operations to perturb the target body's trajectory to
the point where an impact with Earth can be avoided. In the nominal
configuration, each spacecraft will be independently controlled and
powered, but will work in loose coordination with other members of the
network. The spacecraft will be nuclear powered, possibly pre-deployed
outside of low Earth orbit (LEO) (likely an Earth-Moon or Earth-Sun libration point),
and be capable of using chemical propulsive boost to rapidly intercept
an incoming target. Upon arrival, each spacecraft will begin to eject
small amounts of mass from the asteroid that will, over time, slightly
change target's heliocentric (Sun-centered) orbit so that impact is
avoided. SEI's modular approach offers the unique advantages of overall
mission reliability through massive redundancy, economies-of-scale
during spacecraft production, flexible and practical launch and
transfer to an on-orbit pre-deployment location, a tailorable response
depending on the size and nature of the incoming threat, and the
production of only small bits of ejecta that will not independently
survive Earth atmospheric entry. Trade studies conducted by SEI have
assumed that the launch rail that will eject the mined mass from the
impactor (asteroid) should be as long as reasonable, but launch
packaging and stiffness considerations will limit it to no more than 10
meters. As the launch velocity increases for a given shot mass, the
mass driver power increases in a cubic fashion, thus driving up the
size and mass of the mass driver capacitor units. The energy (or work)
used to accelerate the ejecta increases proportional to the square of
the launch velocity, thus requiring a larger spacecraft power supply
(or alternately a longer cycle time between shots) to recharge the
capacitor units. The compressive force on the lander and rail increases
relative to the square of the launch velocity. The downward force will
benefit the mining process to some degree, but an excessive compressive
load would require a massive lander structure and thus exacerbate the
launch and deployment problem for the spacecraft.

Based on these results, SEI has established a working baseline of a
10-meter launch rail, 0.5-kg ejecta mass per shot, and a launch
velocity of 1000 m/s (well within the capability of today's rail
launchers). For this configuration, the ejecta will undergo an
acceleration of almost 5100 Earth g's (gravitational acceleration) for
a period of 0.02 seconds, which means a mass driver power of 12.5
megawatts per shot. [11]

5. Billiards Shot Concept - Artemis target

The billiards shot strategy consists in deflecting a smaller
asteroid (the striker) so that it impacts and destroys the threatening
asteroid before the predicted collision with Earth. The Artemis
asteroid is considered here, which is 119.1 km in diameter, and has the
potential of striking Earth in 2033. The kinetic energy of a small
striker is more powerful than nuclear weapons for the destruction of
big NEOs. Ten tons of nuclear energy is roughly equivalent to 10,000
kilotons of TNT. A 100 meters large asteroid weighs approximately 1
megaton. If the relative velocity at impact is 20 km/s, the kinetic
energy is about 100,000 kilotons of TNT, which is 10 times more than
the energy of a strong nuclear blast. Asteroids as small as 100 meters
in diameter, therefore, could be used for a billiards shot. In the case
of Artemis, a 100-meter diameter asteroid is sufficient. Considering a
plane change maneuver to match Artemis's orbital plane, followed by a
modification of the semi-major axis, it has been shown that the 1999
VK12 is the best striker of the billiards shot against Artemis. The
closest encounter occurs in April 2027. [Note 5]Theoretically, the billiards shot option is cheap in terms of energy;
however the feasibility of the maneuver has yet to be checked. In terms
of energy, it could sometimes be easier to deflect a small striker and
to put it on a collision course with a big target asteroid than to
deflect the latter in order to avoid the collision with our planet. In
the case of Artemis, however, the data are not ideal.

In general, in order to deflect the striker, numerous nuclear blasts
have to be triggered close to it. The striker asteroid should be able
to resist the numerous blasts. It should not be a rubble pile or a
friable asteroid. Since the composition of a potential striker is
usually unknown, a specific mission should be designed to assess its
ability to play the striker role. Complementary studies remain to be
performed to assess astronautic capabilities and to examine the
billiards shot without exact matching of the planes. However, in the
case of a real threat, the billiards shot could be the only option that
allows deflection or destruction of a large NEO (greater than 10 km) at
relatively short notice. [12]

Figure 3: Orbital paths of the Earth (small circular orbit), Artemis
(top), and 1999VK12 (bottom) and positions around the sun in April 2027
[12]

The selection of the best of the above five options depends on the
time available for action and the diameter of the NEO. For space-based
responses, the key parameter is the action time, which is as a function
of the warning time and orbital parameters. Figure 4 is a graph showing
space-based responses. [6]

Figure 4: Selection of the best option according to the action time (in years) and the diameter of the NEO (in km) [6]

B. Earth-Based Responses

Of course, if a successful interception, destruction, or mass
reduction to a safe level of the threatening near Earth object is
impossible due to lack of time or incapability, then Earth based
responses are the only recourse. Earth-based responses can be divided
into two groups depending on the NEO disaster: (1) relocation of the
endangered populations, and (2) sanctuary in appropriate shelters.

If the likelihood of a NEO impact with a particular region of the
Earth is established, the most obvious step is to plan the evacuation
of the population from that zone. Currently there are very few
procedures for coping with this problem, and none at an international
level. The International Strategy for Disaster Reduction (ISDR) is yet
to recognize the NEO threat, although it has procedures to deal with
large-scale disasters on an international level. [22] Furthermore there
is no internationally agreed link in the NEO detection community
between who would give the warning of an impact and these disaster
response authorities. Thus, the time delay between confirmation of a
detection and the official decision makers in government learning of
the threat is probably on the order of days or weeks. The construction
of shelters to protect the population is a last resort that would have
to be attempted in desperate cases. Even in the other cases, in which a
space mission is the main response option, a shelter plan would still
need to be developed as a contingency. [6]

1. Evacuation and relocation

The term evacuation encompasses all emergency efforts to move people
from the area prior to an impact. Depending on the impact's size, the
time scale for evacuations would be hours to weeks. The concept of
relocation refers to a broader effort to save not only humans but
wildlife, cultural heritage, etc., and to establish a temporary or
permanent habitat for them. The time scale for relocation is assumed to
be enough for planning (weeks to decades). [6]

2. Shelters

The 'Shelter' response category refers to any attempts to provide
protection from the effects of a NEO impact on Earth. Depending on the
size of the NEO, there may be 'Long-Term' or 'Short-Term' sheltering.
Long-term shelters are envisioned to sustain human life on Earth after
a large impact has substantially changed the atmosphere and climate.
This is in some ways analogous to attempts at supporting human life on
other planets. Short-term shelters encompass all attempts to mitigate
against the direct effects of the NEO's impact, such as a blast wave,
earthquakes, etc. [6]

IV. Conclusion

It is extremely unlikely that Earth will be hit by a very large
asteroid (size above 1 km) that would cause global destruction, but
chances are much larger for impact with lesser asteroids (100 m or so
in size) that would cause a local catastrophe. A sudden unpredicted
impact may be the most probable scenario due to a currently incomplete
NEOs survey. In terms of risk analysis, the main uncertainty comes from
the incomplete knowledge of the number, size distribution and orbital
parameters of the NEO population. The natural hazard of NEO impact
could be mitigated by adequate advance action. Responding to the
varying magnitudes of NEO threats involves a very broad range of
disciplines and makes the planning for NEO responses a complex task.
However, Earth-based responses to NEO threats can take advantage of
existing natural disaster mitigation strategies applied to earthquakes,
floods, hurricanes, etc. The magnitude of a NEO catastrophe could be
much higher, ranging from a regional to a continental to a global
scale, whereas traditional natural disaster consequences range from
local to regional scales. A major step in assessing any NEO hazard is
to identify the threatening object and to characterize it, either by
Earth or space-based observing facilities, long enough before the
possible impact to design and operate mitigation missions. Most
attention to the NEO threat is currently focused on the detection
issue, and the NEO response work has been almost exclusively on
technology studies of possible space-based strategies. However, the
problem of mitigating the effects of a large Earth-impact having large
regional or even global consequences, and adapting international laws
related to the choice and management of NEO response missions, needs to
be tackled. [6] Given the fact that Earth encounters with near-Earth
asteroids as early as 2027 or 2033 (see above) are possible, the window
of opportunity for planning and organizing for such a possibility grows
narrower with each passing year. In reality, we really don't know with
absolute certainty when the next large asteroid (on the order of that
of the K-T impact) will strike Earth. Therefore, the time to start
preparing is always now.

In a paper delivered at the 2004 Planetary Defense Conference, R. Dale Brownfield of the Gaiashield Group stated:

Any Global Strategic Planetary Defense Policy on this issue must be
firmly anchored in a clear and unmitigated assessment of the threat, an
acute awareness of our current collective inability to reliably deal
with it and a full appreciation of the magnitude of the loss when we do
not. Any rational policy must appreciate that until we have deployed an
effective planetary defense and mitigated this threat, TNLA [The Next
Large Asteroid on its way to strike Earth] is a dire Clear and Present
Danger for the whole world. That this is not just another partisan
campaign issue but a new status quo for mankind requiring
administration by an agency as autonomous and immune to the vagaries of
economics and politics as is possible - a global human martial
authority. In this arena the Mission must dictate the Policy� not the
other way around. Statecraft, Economics and to some degree even Science
must take a backseat to the demands of Planetary Defense. [13]

13. Brownfield, R. Dale, "Waging war on TNLA: The Next Large
Asteroid on its way to strike Earth - A strategic planetary defense
policy proposal" (AIAA 2004-1473, from 2004 Planetary Defense
Conference: Protecting Earth from Asteroids, 23-26 February 2004,
Orange County, CA)

14. NASA, "Near Earth Object Program." http://neo.jpl.nasa.gov

15. Gritzner, C. "Analysis of alternative systems for orbit
alteration of near-earth asteroids and comets", ESA Report no
ESA-TT-1349, 1996. (translation of the original German PhD thesis)

21. "Deflection and fragmentation of near-Earth asteroids", Hazards
due to comets and asteroids, p. 897-924, The University of Arizona
Press, Tucson, 1994

22. United Nations General Assembly Economic and Social Council.
"Implementation of the International Strategy for Disaster Reduction".
Report of the substantive session, Geneva, 2-27, July 2001

23. Holsapple, K.A., 2002, "The deflection of menacing rubble pile
asteroids. In Extended abstracts from the NASA workshop on the
scientific requirements for mitigation of hazardous comets and
asteroids, p. 48-51.

Murray Balsom was trying to launch a weather balloon when a huge
fireball burst across the sky over his small Arctic village of
Resolute. "This was humungous," he said of the gaseous light show he
witnessed 10 days ago.

A
Geminid meteor streaks across the sky against a field of star trails in
this 1 1/2-minute exposure early Dec. 14, 2006, near Willow Beach,
Arizona.

"Had there been a full moon that night, I'm sure it would have
covered three quarters of it. I bet you it lasted six to eight seconds
before it disappeared behind the hill on the edge of town. There were
all kinds of colours bursting out of it. The tail lasted a good two
hours."

Balsom, a hotel worker, was launching a weather balloon as part of
his daily work routine when the fireball burst across the sky over
Resolute, the small Inuit village he lives in.

He wasn't the only person left star-struck by the sight. It also
caught the attention of pilots, meteorologists, miners and the
Department of National Defence.

At first, Balsom thought he was seeing a American spy satellite
being shot down by the U.S. Navy. But when he called his hotel's head
office later that morning, he learned it wasn't the satellite.

That's when he concluded it was a space rock or meteorite crashing
through the Earth's atmosphere - not a UFO, as a few people have
suggested.

"When it finally went down, you could see this big white cloud in the sky that just sat there for the longest time," he said.

"It was the event of the century."

Most meteorites are remnants from asteroids, some from comets. Among the most coveted are those that come from Mars.

Longtime Resolute resident Wayne Davidson was just as ecstatic in describing what he saw.

"The Inuit up here have been on the radio talking about it for days," he said.

An avid skywatcher with a background in meteorology, Davidson
suggested the fireball may have been as big or bigger than the one that
crashed onto frozen Tagish Lake in the Yukon several years ago.

That yielded a cluster of rare carbonaceous chondritese - rare
meteorites that contain both water and organic compounds. Scientists
covet these as clues from the early solar system.

University of Calgary planetary scientist Alan Hildebrand has no
doubt the sighting was spectacular, a once-in-a lifetime opportunity
for anyone who saw it falling. But he doubts that it was big enough to
be crater-forming.

"Meteorites may have fallen to Earth, but the atmosphere is really
too hostile for small falling objects to penetrate to form a crater on
the ground." Without more detailed eyewitness reports, launching a
search in such a large, remote area would be too expensive and unlikely
to produce anything, he said.

By way of comparison, Hildebrand notes, the Tagish Lake fireball
came toward Earth as a 100-tonne space rock. It was so big that its
fiery atmospheric entry allowed scientists to calculate its orbit
before it hit the Earth.

The Tagish Lake space rock exploded with nearly one-tenth the
atmospheric blast power of the Hiroshima nuclear bomb. Had it not been
for a local resident who found some fragments while driving with some
construction materials for his lodge on the frozen lake, scientists
might never have recovered anything.

"I don't want to diminish anyone's enthusiasm for getting excited
about these kinds of sightings," says Hildebrand, "But if they do see
something, they should take note where they were, what time it was, and
what they saw. Then they should report to local law enforcement, search
and rescue, or NavCanada right away."

New Rochelle - In the event that an asteroid or comet would impact
Earth and send rock fragments containing embedded microorganisms into
space, at least some of those organisms might survive and reseed on
Earth or another planetary surface able to support life, according to a
study published in the Spring 2008 (Volume 8, Number 1) issue of Astrobiology, a peer-reviewed journal published by Mary Ann Liebert, Inc. The paper is available free online.

In the report entitled, "Microbial
Rock Inhabitants Survive Hypervelocity Impacts on Mars-like Host
Planets: First Phase of Lithopanspermia Experimentally Tested,"
Gerda Horneck and colleagues describe systematic shock recovery
experiments designed to simulate a scenario called lithopanspermia, in
which microorganisms are transported between planets via meteorites.
The first step of lithopanspermia would involve ejection of the
microorganism-containing rock from the host planet as a result of an
impact event. The researchers sandwiched dry layers of three kinds of
biological test systems, including bacterial endospores, endolithic
cyanobacteria, and epilithic lichens, between gabbro discs, which are
analogous to martian rocks. They then simulated the shock pressures
martian meteorites experienced when they were ejected from Mars and
determined the ability of the organisms to survive the harsh
conditions.

The organisms selected represent "potential 'hitchhikers' within
impact-ejected rocks," explain the authors, and are hardy examples of
microbes that can withstand extreme environmental stress conditions,
write the authors.

The results support the potential for rocks ejected on asteroidal
impact to carry microorganisms capable of reseeding the Earth,
according to Horneck and coworkers, from the Institute of Aerospace
Medicine (Köln, Germany), Humboldt University of Berlin, Heinrich-Heine
University (Düsseldorf, Germany), Ernst-Mach Institute for Short-Term
Dynamics (Freiberg, Germany), Open University (Milton Keynes, U.K.),
the German Collection of Microorganism and Cell Cultures (Braunschweig,
Germany), the Russian Academy of Science (Moscow), and the Planetary
Science Institute (Tucson, AZ).

"Given that impacts have occurred on planetary bodies throughout the
history of our solar system," says journal Editor, Sherry L. Cady, PhD,
Associate Professor in the Department of Geology at Portland State
University, "the hypothesis that life in rock could have been
transferred between planets at different times during the past 3.5
billion years is plausible. These experiments advance our understanding
of the constraints on life's ability to survive the magnitude of impact
that would accompany a meteoric trip from Mars to Earth."

Astrobiology is an authoritative peer-reviewed journal published
bimonthly in print and online. The journal provides a forum for
scientists seeking to advance our understanding of life's origins,
evolution, distribution and destiny in the universe. A complete table
of contents and a full text for this issue may be viewed online.

A US team has won a $50,000 (£25,000) competition to design a
spacecraft to rendezvous with and track the path of an asteroid which
may threaten Earth.

The winning entry, led by SpaceWorks Engineering, will shadow asteroid Apophis for 300 days.

The measurements it takes will be used to refine what is known about
the orbit of this 300m-wide space rock. Apophis will make a close pass
of Earth in 2029 and there is a small but real possibility it could hit
in 2036.

The competition was organised by the Planetary Society, a space
advocacy group with its headquarters in Pasadena, California. The idea
behind the project was to "tag" Apophis and thereby plot its orbit
accurately enough to determine whether it will strike our planet.

The contestants were tasked with designing a mission which would
launch, rendezvous and collect enough data in time for governments to
decide in 2017 whether or not to mount a mission to deflect the
asteroid off its current course.

"We hope the winning entries will catalyse the world's space
agencies to move ahead with designs and missions to protect Earth from
potentially dangerous asteroids and comets," said the Planetary
Society's director of projects Bruce Betts.

On whether space agencies were doing enough to counter the threat
posed by near-Earth asteroids, Mr Betts said: "There is a sense that
generally with space agencies there is not enough being done. Obviously
space agencies have a lot on their plate - a lot of things to choose
from.

"But in this case, we're talking about the one truly preventable natural disaster."

'Long-term focus'

The Foresight spacecraft, designed by Atlanta-based SpaceWorks
Engineering, will rendezvous with Apophis and determine its centre of
mass. The probe will then take regular measurements of its position
relative to the asteroid. These measurements will then be used to
reduce the uncertainties in Apophis' orbit.

"Apophis isn't science fiction, it isn't a blockbuster Hollywood
movie, it is very real," said Dan Geraci, the Planetary Society's board
chairman. "And it's going to test our ability to keep a long-term focus
on something because of the time between now and 2017, 2029 and 2036...
this is a chance to use it as an example of how best to prepare and
build a plan."

Those behind the winning design say they hope to launch the craft in
2012. At the moment, however, the mission exists only on paper.

Second place in the design competition was taken by a team led by
Deimos Space of Madrid, Spain. Third place went to a group from EADS
Astrium in Stevenage, UK. The Georgia Institute of Technology, based in
Atlanta, took first place in the student category, winning $5,000 for
their design.

Urgency

Asteroid 99942 Apophis is a primordial relic from the formation of
our Solar System. It is thought to be made largely of rock and circles
the Sun in an orbit that brings it close to our planet.

In 2029, it will approach the Earth within a distance closer than a
geostationary satellite - and near enough to be seen with the naked
eye. If the orbiting behemoth passes through a "keyhole" in space
measuring several hundred kilometres wide during this pass, it will
strike Earth in 2036.

Earth-based observations might not be sufficient to rule out an impact in 2036.

Planetary defence advocates say it is imperative to collect data on
the asteroid's path as soon as possible to know whether it will strike
our planet or not. If it is found to be on a collision course, one
option governments have is to mount a deflection mission. This would
involve launching a spacecraft able to give the asteroid a nudge to
change its orbit.

Leaving this too long would make it impossible to build a spacecraft
powerful enough to move its out of harm's way. Ideally, say advocates
of such a mission, Apophis' orbit would need to be changed before 2025
to be sure it misses the Earth.

Nasa estimates that if Apophis were to hit Earth, it would explode with as much energy as 400 megatonnes of TNT.

3 comments:

Paul Crawford
said...

It was an early evening in 1969 or 1970. I was indoors attending a game between UTEP and the Globe Trotters in El Paso, Texas (time, date line). Suddenly there was a very loud screeching sound similar to a very low-flying jet fighter moving at high speed from approximately north to south. I heard later that it was a meteor that fell to earh in northern Mexico. I have searched, but have never been able to find a media reference to the event. Can anybody provide a reference?

While waiting at the polling site during the presidential election of Ronald Reagan, Nov.4, 1980 I observed a huge fireball with several dark balls in it. It covered the entire sky where I was on Imnaha, Oregon. Another party coming to vote mentioned it when he went in to vote also. I was so amazed, at first I thought the booms and fire balls were celebration of the election! I turned on the radio in the car and heard that a fireball had been sited in Washington just prior to my seeing it. Did anyone else re port it? I have searched to no avail for any mention.